* Lap 1: After qualifying on pole position for the first time this year – and the fourth in his Formula One career – Kimi Räikkönen makes a clean start to head world championship leader Fernando Alonso into Tamburello and establish a clear lead. Jenson Button grabs third from Jarno Trulli. Takuma Sato is initially fifth, but Mark Webber passes him around the outside of Tosa and makes it stick. Alexander Wurz heads the rest, from Jacques Villeneuve, Rubens Barrichello, Nick Heidfeld, Giancarlo Fisichella, Ralf Schumacher, Michael Schumacher, Red Bull newcomer Vitantonio Liuzzi, David Coulthard, Narain Karthikeyan, Tiago Monteiro, Felipe Massa (who qualified eighth, was relegated to 18th after a pre-race engine change and was then slowest away initially), Patrick Friesacher and Christijan Albers.

* Lap 2: Massa passes Monteiro for 17th.

* Lap 3: Pulling away, Räikkönen laps in 1m 23.347s – his best yet.

* Lap 4: A queue is beginning to form behind Trulli, with Webber at its head. Massa passes Karthikeyan for 16th.

* Lap 5: Räikkönen leads by 3.1s.

* Lap 6: Fisichella slides out of 11th place at Tamburello and crunches into the tyre wall.

* Lap 8: Räikkönen ups the pace again – 1m 23.296s. Massa has a peep down Coulthard’s inside at Rivazza, but decides against it.

* Lap 9: Räikkönen slows suddenly and cruises back to the pits as Alonso sweeps into the lead.

* Lap 11: Alonso sets the race’s fastest lap so far – a 1m 23.223s – and is almost 10 seconds clear of Button. Trulli continues to be shadowed by Webber and Sato, with Wurz and Villeneuve edging closer.

* Lap 14: Button laps in 1m 23.380s – his quickest yet – but remains 9.4s adrift.

* Lap 16: Massa wipes off his nose wing against Coulthard’s rear wheel at Rivazza. The Brazilian heads to the pits for repairs and rejoins 16th.

* Lap 17: Barrichello pits from eighth.

* Lap 18: Barrichello peels in again – this time to retire.

* Lap 20: Monteiro makes his first stop. Albers retires. Button cuts the fastest lap to 1m 23.163s…

* Lap 21:…and 1m 22.872s. Heidfeld, Ralf S and Kathikeyan pit.

* Lap 22: Sato repasses Webber at Tamburello to claim fourth. Trulli and Webber pit.

* Lap 23: Alonso, Sato and Villeneuve come in.
 
* Lap 24: Button pits. In clear air for the first time, Michael S laps in 1m 22.287s, which rather puts everything else into context.

* Lap 25: Wurz and Coulthard stop.

* Lap 26: Michael S laps in 1m 22.070s.

* Lap 27: Michael S and Liuzzi are the last drivers to refuel.

* Lap 28: Alonso leads by 10 seconds from Button – and 31.6 from Michael S. After gaining ground at the stops, Wurz is fourth from Sato, Trulli, Webber, Villeneuve, Heidfeld, Ralf S, Liuzzi, Coulthard, Massa, Kathikeyan and Monteiro.

* Lap 29: Michael S laps 1.7s faster than Alonso. The chase is on.

* Lap 30: Villeneuve passes Webber after the latter runs wide. Michael S takes another 1.2s out of Alonso and establishes an enduring pattern.

* Lap 32: Michael S helps himself to another 1.8s…

* Lap 33: …and 1.9s.

* Lap 36: Coulthard and Massa clash again at Rivazza: the Scot runs wide and Massa moves up to 12th.

* Lap 40: Monteiro pits.

* Lap 41: Massa refuels.

* Lap 42: Alonso, Webber and Karthikeyan come in.

* Lap 43: Button leads Michael S by 0.4s.

* Lap 44: Heidfeld and Ralf S pit.

* Lap 45: Trulli stops.

* Lap 46: Sato, Villeneuve and Coulthard come in.

* Lap 47: Michael S passes Button as they approach slower traffic at the Variante Alta. Wurz and Liuzzi pit.

* Lap 48: Michael S laps in 1m 21.858s. Button pits.

* Lap 49: The leader refuels and rejoins with Alonso in his sights. Monteiro pits again. Post-stops, Button runs third from Wurz, Sato, Villeneuve, Trulli, Ralf S, Heidfeld, Webber, Liuzzi, Massa, Coulthard, Karthikeyan and Monteiro.

* Lap 50: Alonso leads by 0.3s – which is about as much of a cushion as he will get between now and the end of the race.

* Lap 52: Monteiro pits again, not that anyone’s looking.

* Laps 53-59: The top two continue to circulate absolutely as one.

* Lap 60: Michael S gets very close at Tosa, but Alonso repels the challenge. There is just 0.2s between them at the end of the lap – the closest margin yet.
 
* Lap 62: Michael S has another go at Tosa, is too far adrift to have a pop at Rivazza and finally crosses the line 0.2s behind the world championship leader. They exchange a friendly wave. Button takes his first podium of the year from Wurz, Sato, Villeneuve, Trulli and Ralf S. Liuzzi finishes 11th on his F1 debut, two places ahead of team-mate Coulthard.