On the left, Romain Grosjean muscles Lewis Hamilton on to the grass
Button seizes the lead as Hamilton and Grosjean collide
Grosjean's Lotus is pitched skywards as he slams into Alonso's Ferrari
Alonso goes flying, while Hamilton clips poor Kobayashi's Sauber
Championship leader Alonso was an innocent casualty of the accident
Hamilton won the last race in Hungary, but barely started this one
The Briton pops over to have 'a quiet word' with his assaulter, Grosjean
Sergio Perez qualified a best-ever fourth, but lasted just 250 metres
The DRS zone, which started at the top of Eau Rouge, prompted action
Button salutes his McLaren team from the top step of the podium
McLaren's Jenson Button bounced back to form with a convincing win in the Belgian Grand Prix at Spa-Francorchamps today.
The Briton banished memories of a recent slump in performance by qualifying on pole position and speeding into an immediate lead at the start as chaos erupted behind him. Lotus driver Romain Grosjean chopped across the track from left to right and clipped the second McLaren of Lewis Hamilton, triggering a savage multi-car shunt that eliminated Fernando Alonso and Sergio Perez.
Also involved was a heartbroken Kamui Kobayashi, who had lined up on the front of the grid for the first time, but made a poor getaway and was an innocent victim in the shunt. Although he was able to rejoin after a pitstop, his Sauber was missing some bodywork parts and its aerodynamics were affected.
When the race got back underway following a lengthy clear-up operation, Button continued to pull away as several battles for position developed behind him. The fickle Ardennes weather had left teams short on dry-track running, and several different strategies and car set-ups mixed up the race order.
Button aside, the stand-out performer was world champion Sebastian Vettel. The Red Bull Racing driver started tenth on the grid, but drove an aggressive race to move up to second position by the end. Vettel and Button were the only competitors to make a one-stop strategy work; other drivers who attempted it suffered severe tyre wear in the closing stages of the race and lost time.
Behind the top two, Kimi Räikkönen completed the podium for Lotus. In the early laps the feisty Finn looked as if he might challenge Button for victory, but he faded slightly as his Renault-powered car developed a problem with its Kinetic Energy Recovery System (KERS) and his tyres lost grip. He did, however, pull the overtaking move of the race – slicing past Michael Schumacher on the run down the hill to the daunting Eau Rouge in the closing laps.
Nico Hülkenberg gave Force India a huge fillip by running strongly to fourth place. The German and team-mate Paul di Resta benefited from the first-corner melee to move up to third and fourth places, but di Resta was compromised by a non-functioning KERS. He eventually finished tenth.
Felipe Massa turned in one of his strongest performances of the season to claim fifth for Ferrari, ahead of Mark Webber. Michael Schumacher - starting his 300th grand prix at the track where he made his debut 21 years ago – ran third in the early stages but experienced excessive tyre wear and drifted to seventh.
Scuderia Toro Rosso had a strong race and got both of its drivers into the points. Jean-Eric Vergne was eighth, just ahead of Daniel Ricciardo.
With championship leader Alonso retiring for the first time this year, Vettel has gained ground on him and is 24 points in arrears as the F1 circus moves to Monza for the Italian Grand Prix next Sunday.
Belgian Grand Prix, round 12/20, 2 September 2012
1 Jenson Button (McLaren)
2 Sebastian Vettel (Red Bull)
3 Kimi Räikkönen (Lotus)
4 Nico Hülkenberg (Force India)
5 Felipe Massa (Ferrari)
6 Mark Webber (Red Bull)
7 Michael Schumacher (Mercedes)
8 Jean-Eric Vergne (Toro Rosso)
9 Daniel Ricciardo (Toro Rosso)
10 Paul di Resta (Force India)