0km - Bradley Wiggins crossed the line 3:37 minutes down - but it's yet to be confirmed if his time will be taken at the 3km mark or at the finish. Either way, that is his chance of winning the Giro well and truly over.
0km - A superb lead out by Gert Steegmans there to set up Cavendish, who easily took the win ahead of Nacer Bouhanni of FDJ and Luca Mezgec of Argos Shimano.
0km - Mark Cavendish with one of the easiest wins of his career - pretty mich uncontested. And that's the 100th win of his career.
0.5km - Heartbrak for the break - Felline and Marcato try until the death, but the pack zips by...
1km - I spoke too soon - they are still out ahead of the pack. But not for much longer... although will they hold on? We're into the final kilometre now!
2km - It's all over for the break - game on for the bunch sprint.
2.5km - Lotto have sent men forward for Kenny Dehaes. But it's surely going to be Cavendish vs local boy Viviani here.
3.5km - Just 12 seconds now - and the GC time will be taken soon when the pack passes under the 3km kite.
5km - Just five to go for the leaders - but they won't be able to hang on. Now it's a question of whether we can have a clean, incident-free sprint.
6km - Cannondale and OPQS both want this stage. They combine to reduce the gap to 25 seconds for the break. The Wiggins/Team Sky group is only just passing through the finish area.
7km - Sky have confirmed that Uran is in the peloton and so not in the Wiggins group.
8km - It's the first sight of the finish line for the riders as they pass through ahead of the final circuit around Treviso.
9km - Just 30 seconds now for the break, with the Wiggins chasing group a further 2:30 back.
10km - Race radio says that Rigoberto Uran is not with the main pack either. If that is the case then this is an utter nightmare for Sky.
12km - The gap is less than a minute for the five escapees so they will soon be swept up by the pack, which is being driven forward by Omega Pharma-Quick Step. Lampre, Movistar and GreenEdge are fairly active too.
13km - So there was some confusion there: Wiggins was surrounded by team-mates but he was dropped from the chasing group off the back of the peloton. He was riding in isolation but then Knees came back, followed by his other team-mates. Uran is not there so the Colombian will be the No.1 at Sky from now on.
15km - It seems that Sky have ruled their riders to leave Wiggins behind because the 2012 Tour winner is now on his own inside that chasing group. Actually, he now has Christian Knees - but the gap is now two minutes back to the pink jersey group.
17km - The five escapees have 1:30 over the main pack and 2:05 over the Wiggins chasing group. It looks like it's coming back together as the rain continues to pound down.
20km - The Wiggins group is 1:15 down on the main peloton. No news of which Sky riders are with him - presumably Rigoberto Uran is not. The Colombian may be top dog at Sky from now on. With the times being taken at 3km today, Wiggins only has 17km to make this back.
21km - Bradley Wiggins is off the back of the peloton and surrounded by Sky team mates. This has been a regular occurance in this year's Giro and the British rider is clearly suffering once again today. They must have lost contact on the descent.
22km - The rule of thumb is a minute for ever 10km. The gap still has 2:10 and so this will be touch and go.
25km - Most riders are going for the cap 'n' helmet combo today because sun glasses aren't so effective in the rain. There's a slight split in the peloton - with Michele Scarponi in the second group, as well as some of the Sky riders. But the gap is not huge and it will come back together.
29km - The gap is still 2:30 and no other team has yet moved to the front of the peloton to help out Omega Pharma-Quick Step. It's not so much of a surprise - their man Cavendish already has two wins and so they can jolly well work for a third.
30km - Belkov is the only rider in this group to taste victory in not only the Giro but any Grand Tour. Marcato has a host of wins, including last year's Paris-Tours, while his team-mate Lammertink is the youngest in the break at just 22 years of age.
32km - A reminder of the five breakaway riders: Fabio Felline (Androni-Giocattoli), Maxim Belkov (Katusha), Bert De Backer (Argos Shimano), Maurits Lammertink and Marco Marcato (both Vacansoleil-DCM). Felline is the best-placed rider on GC but the Italian is nevertheless 54:22 down on race leader Vincenzo Nibali.
35km - There's a fair lot of debris on the road - leaves, twigs and small branches - which the peloton has to dodge on the way down. Up front, De Backer has pulled out ahead of his fellow escapees - he's the only one who hasn't fallen today and so it's understandable the 29-year-old Belgian has a bit more cofidence on this descent. This is De Backer's debut in any Grand Tour. A win would be nice...
38.5km - Now time for the bit that Bradley Wiggins hates: the wet descent... Lucky for the Sky team leader, it's not a steep one and should pose too much difficulty.
39km - Omega Pharma-Quick Step are tapping out the tempo as they crest the summit 2:39 down on the five escapees.
41.5km - Maxim Belkov (Katusha) leads the break over the summit to take the points ahead of Marcato and Felline. Earlier we saw a man in a Father Christmas costume, which was fun. Back with the peloton, Pablo Lastras (Movistar) has a problem and needs a wheel change.
42km - Belkov is driving the break up this climb, which gets really muddy and miserable towards the top. There are no spectators without umbrellas - this is the worst we've seen it all week.
43km - Quite a few riders will be tailed off on this climb because it's pretty punchy - even more so in this torrential rain. The roads are narrow and the grass verges very slippery and muddy. Mark Cavendish is on the front of the pack, keen not to be one of those rides who falters.
44km - The leading quintet are onto the Cat.4 Montello - Santa Maria della Vittoria - a 3km climb at 6.3% with a maximum gradient of 14%.
45km - Cadel Evans is riding safely near the front of the peloton, protected by his British BMC team-mate Steve Cummings. Evans always looks like he's in pain and suffering - with that lopsided head and snarl above the cleft chin - so it's hard to tell how he's finding this relentless rain.
48km - Should it come down to a sprint between the escapees then you'd have to fancy Fabio Felline - the 23-year-old Italian has quite a kick. Although there will be no pressure on Belkov, already a winner in this year's Giro. For the numbers game, you'd fancy Vacansoleil for they have two riders and a strong finisher in Marcato. But then again, Bert De Backer is the only of these five riders not to taste the tarmac today...
50km - You have to feel for the five escapees, who are clearly doing all this hard work in vain. Today has been the shortest road stage of the race so far - but with all the rain, it will have felt like the longest for many.
53km - Of course, a Cavendish win is not a given: before the finish there's the tricky Cat.4 climb which is just coming up. Some of the sprinters could be tailed off - although with a 30km run into Treviso, you'd think they'd be able to fight back on before the finish.
55km - Lammertink pips Belkov to the second intermediate sprint to pick up the small prize, plus bonus seconds and red jersey points. It's Cavendish who wants to be back in red tonight - although even if he wins, Elia Viviani may be in red should he finish second or third. This is all presuming that Cadel Evans will take it easy over those last 3km when the stage times are neutralised - which is the likely scenario.
56km - Quite a few of the rain coats have come off now - including that of Mark Cavendish.
57km - The lead is down to 2:20. Australian Jack Bobridge (Blanco) has been on the back of the peloton for quite some while now. At the moment, he's trying to follow the wheel of Canadian defending champion Ryder Hesjedal (Garmin-Sharp), whose race has been almost as bad as the weather. He shipped 21 minutes in the first major mountain stage and is now surely only riding in a bid to regain form and fitness ahead of the Tour.
60km - Colombian rider Dalivier Ospina (Colombia) has pulled out of the race. He's been strruggling with illness and this weather is proving a bridge too far for the Giro debutant.
64km - It's been confirmed that the times will be taken from the 3km mark today - so that any splits in the peloton will not be taken into account. That means that only those who are keen to win the stage - the sprinters and their lead-out trains - will need to put their heads on the line. The others can just coast through Treviso and soak (!) up the atmosphere.
65km - Marco Marcato takes off his leg warmers. There's so much water they were probably weighing him down. It's not actually that cold here in north Italy - nothing like Milan-San Remo earlier in the season.
66km - Mark Cavendish looks understandably miserable in this monsoon. It's his OPQS team-mate Gianluca Brambilla who is setting the pace on the front of the pack. Do you reckon Cavendish will win today to make it three wins? Or can someone like Nacer Bouhanni (FDJ) or Elia Viviani (Cannondale) spoil the Manx party?
68km - Vacansoleil-DCM team-mates Marcato and Lammertink will hope to cause an upset and get the win today - and in doing so prove a point to their departing team sponsors. The route has a bunch sprint written all over it - but in such terrible conditions you never know what may happen. The gap is 2:50.
70km - Daniele Bennati of Saxo Bank needs a bike change. The Italian from Saxo Bank is an outsider for today's stage - although this VERY. LONG. bike change won't do him any favours. Really, this is amateur stuff from Bjarne Riis's team - he's been waiting for over a minute and the ride back on will be long and tiring.
76km - Marcato takes the maximum three points over the summit and there's nothing left to play for then the peloton crosses three minutes later. There's no change in the KOM standings, with blue jersey Stefano Pirazzi leading on 46 points, followed by Jackson Rodriguez (26) and Robinson Chalapud (23).
77km - This climb is used in the Italian national championships and although it's a "wall" it's not too daunting. After that crash earlier, both Belkov and Marcato changed their bikes. The Russian forgot to take his computer powermeter off his old steed and so he's riding 'au naturel' now.
78km - The leaders are onto a little climb through some vineyards. It's the first of the two categorised climbs that are on the menu: the Cat.4 Muro di Ca' del Poggio (1.2km at 12.2% with a maximum gradient of 16%). The gap is now 2:45.
82km - A red flag is being waved by a race motorbike. Usually that signals the neutralisation of the stage and so it's all a bit confusing. The race goes on, however. Perhaps it was a warning to the riders ahead of a slippery stretch of road.
90km - Today’s stage finishes with two laps of a circuit around Treviso – or at least, that’s the plan. Eurosport commentator thinks that the race organisers may well scrap the last 7.5km loop because of all this rain. The fear is that with the teams of the sprinters taking risks in placing their men towards the front, there could be a large accident. The problem is that should they scrap the lap, there’d only be the same problem 7.5km earlier, surely?
93km - The lead is 3:20 is for the escapees as the Omega Pharma-Quick Step team of Mark Cavendish come to the front of the peloton. They’ll want to set their man up for a third win. Off the back, Wiggins is riding very gingerly. He hates the rain and he’s riding with a chest infection too. Astana have come to the front to help pace setting – they must know that Wiggo is struggling.
96km - No sign of Marcato in the break at the moment so perhaps the Italian was hurt in his part in the synchronised fall. Belkov has taken off his rain jacket now. Hard man. Regarding Marcato – false alarm: he’s now back.
98km - The pace has slowed considerably in the peloton as news of that incident filters through. They will be aware of the break’s fate. It’s Cannondale who are taking responsibility and setting the pace. But Wiggins is not happy – the 2012 Tour champion has already struggled on wet descents earlier in the race and he’s now hanging out with the Colombia riders at the back of the pack.
100km - CRASH: Four of the five escapees all hit the deck after sliding on the wet road. Belkov was leading the way and came down first and then the others came down like dominoes. Bert De Backer is the only rider not to hit the deck there. But they’re all back up and on their way.
103km - The gap is up to almost three minutes for the five-man break. It’s so dark out there it could almost be night.
106km - Maglia rosa Vincenzo Nibali looks utterly miserable back in the peloton as he chats to a rider from Lampre-Merida. You can tell Nibali is from Astana because of his blue shorts – but there’s no sign of his pink jersey because he’s in the ubiquitous black rain jacket. Some teams have jackets that reflect their team colours – Vini Fantini and Cannondale, for example, who sport their same garishly fluorescent yellow and lime green colours.
112km - Belkov is piling on the pressure on the descent. The Russian 28-year-old did just this in stage 9 a few days ago – which he won after attacking climbers Stefano Pirazzi and Robinson Chalapud on a long downhill. Even this hellish weather isn’t putting the Katusha man off.
114km - De Backer taps Belkov on the arm and the two combine in an attack off the front of the break – something that was clearly prearranged between the two riders. It’s Belkov who takes the maximum points at the first intermediate sprint – which in fact has come at the top of a gradual climb – ahead of De Backer and then the others. But it comes back together as Marcato finally makes the connection.
115km - The continued shoddy weather won't help Bradley Wiggins, who announced yesterday that he has been riding with a chest infection. "I'm not feeling very good at the moment, I've had a pretty rough 24 hours. I've got a chest infection and a bog-standard head cold. Fortunately in these days, these kinds of stages, there's just a bit of fighting and you can get through them and hide a little bit. But I just want to try and fight through it and hope that in a few days' time I'll be all right."
118km - The rain is almost Apocalyptic - and news from the finish in Treviso is that it's even worse. The vast majority of the peloton are wearing black jackets although Lammertink is going for just a sleeveless gilet. Shoe covers are the order of the day too - although not for De Backer, who must have thoroughly sodden and cold feet.
120km - The four riders have 1:30 over the peloton with Marcato about to join them. The Italian is just 20 seconds down and will soon make the connection.
122km - Marco Marcato of Vacansoleil-DCM is riding in pursuit of the leading group in a bid to join his team-mate Lammertink. With both Vacansoleil and DCM pulling out of sponsoring the Dutch squad, its riders have a lot to prove amid the uncertainty surrounding their futures.
124km - BREAK: Four riders have defied this horrific weather to made a move. They are: Fabio Felline (Androni-Giocattoli), Maxim Belkov (Katusha), Bert De Backer (Argos Shimano), Maurits Lammertink (Vacansoleil-DCM)
125km - Mark Cavendish is the big favourite today to make it a hat-trick of wins on this year's race. Should the Omega Pharma-Quick Step sprinter take the victory he could well move back into the lead of the red points jersey standings. But he'll face stiff competition from Italian Elia Viviani, who currently trails points leader Cadel Evans by 13 digits. Cavendish is two points further back so there is a lot to play for.
130km - It's a grim day in north Italy with the rain pounding down and a temperature of just 13 degrees Celsius.
134km - They're off! On the agenda today: two punchy Cat.4 climbs and then a flat run into Treviso for what promises to be a bunch sprint finale.
13:15 - There has been a slight delay to the start of the stage because of a bus blocking the road - but the remaining 191 riders are about to get the race under way. One non starter today - Matt Breschel of Saxo Bank has called it a day because of a knee injury.
13:10 - There was no change in the GC yesterday. Italy's Vincenzo Nibali leads Australia's Cadel Evans by 41 seconds with Rigoberto Uran third at 2:04 and his team-mate Bradley Wiggins one second further back in fourth. Dutchman Robert Gesink completes the top five at 2:12.
13:05 - Yesterday, Lithuania's Ramunas Navardauskas restored some pride to the Garmin-Sharp squad of faltering defending champion Ryder Hesjedal with a strong solo win in stage 11. Navardauskas dropped fellow escapee Daniel Oss (BMC) on the second of two climbs with 5km remaining of the 182km stage from Tarvisio to Vajont to set up the biggest win of his career.
13:00 - Welcome to LIVE coverage of stage 12 of the Giro d'Italia - a short 134km ride from Longarone to Treviso that should give the sprinters a rare chance to get a slice of the action.