Strategic victory for Button

Jenson Button profited from another canny tyre strategy to win the Chinese Grand Prix on Sunday, beating his teammate Lewis Hamilton in a 1-2 finish for McLaren, writes Chris Lines.

Button, the reigning world champion, vaulted to the top of the Formula One championship by employing some cool-headed decision making amid the chaos of changing conditions which forced most drivers to pit at least four times. Button, by contrast, made only two stops.

Rain began to fall just before the race started, yet all cars started on dry-weather tyres. A dampening track soon forced a critical decision. Many of the leaders elected to change to wet-weather tyres after a couple of laps, while Button, and third-place finisher Nico Rosberg chose to stay out on dry-weather tyres.

Drivers who had changed to wet-weather ones soon found the treaded tyres were degrading quickly and after three or four more laps, returned to the pits to change back. That allowed Button, Rosberg and Renault's Robert Kubica to dash well clear in front.

"It was my best race victory," Button said. "This one was pretty special because it was very tough conditions.

"It was a tricky race out there and again we called it right," Button said. "It was not just about being quick, it's about reading the conditions."

Hamilton was among those forced into a double pit early, but charged through the field from ninth after nine laps to second after 39. He looked capable of overtaking Button, who ran off the track with five laps to go as his tyres wore away, but Hamilton's tyres also soon became unmanageable.

"It was really the wrong call for us and it ruined the race a little bit," Hamilton said of the decision to switch tyres twice early. "It was definitely an exciting race. To climb my way back up to second was great."

Rosberg led until lap 19 when he ran wide on his worn tyres and allowed Button through. Late in the race, when all the drivers' tyres were worn, Rosberg was challenged by Fernando Alonso, but the German held firm and kept the Ferrari driver in fourth.

Alonso led into the first corner of the race, but was soon penalised for jumping the start and given a drive-through penalty. That sanction, plus his four tyre changes meant the Spaniard made five trips to the pits.

His compatriot, Toro Rosso's Jaime Alguersuari, outdid that with six visits - one short of the F1 record, illustrating how hard it was for teams to read the track and the changing conditions.

Renault's Robert Kubica finished fifth and his teammate Vitaly Petrov earned his first F1 points by taking seventh. Separating the Renault pair was pole-sitter Sebstian Vettel. The Red Bull driver was shuffled back by his hasty change to wet tyres and then back to dry ones, and was never in contention.

His Red Bull teammate Mark Webber made the same strategy error and finished eighth, ahead of Ferrari's Felipe Massa and Mercedes' Michael Schumacher, who again struggled for much of the race, forced into defensive driving to hold off quicker rivals.

After four races this season, Button leads the drivers' standings on 60 points, ahead of Rosberg's 50. Hamilton and Alonso are level on 49 in third.

McLaren also took over the lead in the constructors' standings, with 109, ahead of Ferrari with 90. Mercedes jumped to third with 78, ahead of Red Bull with 73.

The race also featured two pit lane incidents. The first saw Hamilton and Vettel race in the entry to the pits, and after their stops the pair drove wheel-to-wheel along the pit lane, prompting a stewards' investigation.

The second incident involved Alonso passing teammate Massa on the tight pit entry.