MONTREAL (Reuters) - Lewis Hamilton went from hero to zero on Sunday after crashing into Ferrari's world champion Kimi Raikkonen in a bizarre pit-lane pile-up at the Canadian Grand Prix.

The 23-year-old McLaren driver, who covered himself in glory by winning in Monaco two weeks ago, kissed goodbye to his championship lead with the most embarrassing moment of his fledgling Formula One career.

To make matters worse, Hamilton collected a 10-place penalty on the starting grid for the next race in France in two weeks' time.

Leading the race from pole position at the scene of his first grand prix victory last year, Hamilton ploughed into the back of Raikkonen's stationary Ferrari after they pitted on lap 20 while the safety car was deployed.

The Finn had stopped at the red light at the end of the pit lane, with BMW Sauber's Polish driver Robert Kubica waiting alongside for the all-clear to rejoin the race.

Hamilton failed to brake in time, with German driver Nico Rosberg then adding to his misery by shunting the McLaren with his Williams.

"We got into the pitstop, it wasn't a great stop and I saw the two guys in front of me and they were battling in the pit lane," Hamilton told ITV television.

"I was obviously trying to make sure I didn't get involved with those guys. I saw the red light but by the time they had stopped and I had seen the red light it was a bit late," he continued.

"It's a lot different if you crash into the wall and you are angry with yourself. It's not like that. I apologise to Kimi if I've ruined his race but that sort of thing happens."

IRONIC TWIST

Hamilton, who had been three points ahead of Raikkonen at the top of the standings before the start, climbed out of the wrecked car and exchanged a few words with Raikkonen before walking back to the McLaren garages without removing his helmet.

In an ironic twist, Raikkonen had failed to score points in the previous Monaco Grand Prix after driving into the back of Adrian Sutil's Force India in the closing minutes while the German was in a stunning fourth place.

Raikkonen said Hamilton's error was of a very different kind, however.

"I'm not angry but what Hamilton did was inexplicable. More, it was stupid," he told Italian television.

"I'm not the right person to talk about a shunt, given what happened in the last race but it is one thing to collide on the track in the heat of the race and another in the pit lane when you are stopped at a red light," he said.

While Raikkonen fumed, Kubica went on to take his first grand prix win and move four points clear of Hamilton in the championship.

That marked a complete reversal of last year's race in Montreal, where Hamilton celebrated his first Formula One win while Kubica crashed heavily and ended up in hospital fortunate to have escaped serious injury.

Sunday's incident also completed a bad week for the Hamilton family - Lewis's father Anthony crashed a borrowed Porsche in England and the F1 driver had even joked about the incident on television before the race.

"I've just been laughing. It's bad of me, I shouldn't but I said 'Dad, how do you crash a car at 30 miles an hour?'"

(Reporting by Simon Evans; editing by Alan Baldwin)