After two disappointing races at Valencia and Silverstone, McLaren will be under pressure to perform at this weekend's German Grand Prix — but why have they slipped back and how can they recover?
It seems like an age since the McLaren team was cheering Lewis Hamilton across the line as he took an impressive victory in the Canadian Grand Prix - but just two races have passed since then and talk is now of McLaren's season going from potential triumph to potential disaster.
It shows how fickle Formula One is in 2012.
A look at a championship chart shows that although McLaren took the lead with the most points in the opening race, over the opening three races they were scoring points at a similar rate to Red Bull. After that, the reigning champions maintained the momentum but McLaren's pace stalled and their scoring rate dropped on to a level similar to Mercedes, flattening off more in the most recent two races.
The cumulative driver points show how much Button's poor performances are hurting McLaren's tally — with Hamilton more or less matching the Red Bull pair and Ferrari's Fernando Alonso for points until the last two races, when Hamilton's scoring rate also dropped off.
Alonso has made a strong challenge at the front but that is through his race performances making up for inconsistent qualifying — his surprise (damp-affected) pole at Silverstone, for example, came immediately after he failed to reach Q3 at the preceding race in Valencia.
Red Bull have recently become strong in qualifying and comparing their one-lap performance relative to McLaren's in a chart also shows clearly how the advantage has switched — with McLaren's performance at Silverstone marking a season low.
The next two weeks offer the Woking team two crucial opportunities to get the positive momentum back before the summer shutdown — but they need to get walking again before they run.
McLaren have admitted they are pushing so hard they aim to introduce new parts that give one-tenth of a second improvement at every race — and bad Fridays in recent races have put them on a major back foot.
Back in Canada, Hamilton had a strong Friday — which helped set up his successful weekend — but Button suffered an oil leak in the morning session that also hampered his afternoon runs and because the two drivers run quite different set-ups, he struggled for the rest of the race weekend.
In Valencia, McLaren blamed unexpectedly gusty winds on the Friday for causing them set-up problems, while the Silverstone rain put paid to any reliable Friday running.
That means that, if the development pace is to be believed, then by the time the next update comes this weekend McLaren should have found three tenths of a second since Canada.
They haven't shown that in the last two races — but that doesn't mean the improvement is not there, it could just be that the missed Friday sessions mean those previous two steps haven't been optimised yet.
In an ideal world, of course, engineering development is done methodically, with each step evaluated against its predecessor to determine whether that particular development has made an improvement.
Which is why McLaren have a very busy Friday ahead of them in Germany.
With Silverstone turning out to be such a disaster, they will have delved deep into the data to find out why. But they should evaluate those previous developments properly before trying out the additional changes and then setting up the car for the track.
They have already made an effort to merge the two drivers' styles so they can work as a team and help develop the car together — and that could be crucial on Friday.
They will need both cars, possibly doing back-to-back tests, to run well on Friday to get a real understanding of whether they are heading in the right direction. And if they can recover that lost time, they could soon be right back in the mix.