Lewis Hamilton held on to a dominant Italian Grand Prix victory after he escaped escaped sanction in a post-race investigating into Mercedes' starting tyre pressures. The Briton took his seventh victory of the season in Monza, with the Mercedes driver beating Ferrari’s Sebastian Vettel to the flag by 25 seconds.

The Briton had been cruising in the final stages of the race when, with a handful of laps remainning, he was suddenly told to increase the 19-second gap he had in hand over Vettel.

"We need to pull a gap, don't ask questions, just execute," said his race engineer, who informed Hamilton that all would be explained after the chequered flag.

The issue stemmed from tests on the grid, inside the five-minute-signal before the start, that had revealed that the left-rear tyre of Hamilton’s car and that of team-mate Rosberg had tyre pressures below the minimum starting pressures specified for the weekend. Hamilton’s tyre was 0.3psi below the specification, while Rosberg’s was 0.6 under the required mark.

However, after the investigation the team was found not to be at fault for the transgression with the stewards stating that “the pressure in the tyres concerned were at the minimum start pressure recommended by Pirelli when they were fitted to the car.”

The stewards added that “the tyre warming blankets had been disconnected from their power source, as is normal procedure, and the tyres were significantly below the maximum permitted tyre blanket temperature at the time of the FIA’s measurement on the grid, and at significantly different temperatures from other cars measured on the grid.

“Further, the Stewards are satisfied that the team followed the currently specified procedure, supervised by the Tyre Manufacturer, for the safe operation of the tyres.”

Third place in the race went to Williams’ Felipe Massa who inherited the position less than two laps from the chequered flag when the engine in Nico Rosberg’s Mercedes failed. Ferrari’s Kimi Raikkonen who stalled on the front row of the grid at the start and dropped to the back of the field recovered to finish in fifth place behind the second Williams of Valtteri Bottas. Sergio Perez was sixth for Force India, while team-mate Nico Hulkenberg took seventh. Red Bull Racing’s put in a battling drive to climb from 19^th place on the grid to take eighth place and the final points positions were occupied by Sauber’s Marcus Ericsson and the second Red Bull of Daniil Kvyat.

When the lights out went out at the start Hamilton made a good getaway to take the lead but second on the grid Raikkonen stalled and was swamped by the cars behind. Vettel took second but Rosberg made a bad start and dropped to sixth from fourth as he was passed by Massa, Bottas and Perez.

Further back, Toro Rosso’s Carlos Sainz made a good start to climb to 11^th place by the end of the first lap, as did Red Bull Racing’s Daniel Ricciardo, who made his way from 19th on the grid to P13 as lap two started.

Raikkonen dropped to the back of the field but was soon back in the battle for points as Verstappen served an early drive-through penalty and Pastor Maldonado pitted and then retired. His Lotus team-mate Romain Grosjean was in trouble as well and the Frenchman pulled over from P7 and retired from the race on the second lap. Raikkonen was thus quickly promoted to P11 by lap three behind Sainz.

At the front Hamilton began to swiftly pull away and by lap the end of lap eight he had carved out a 4.5 second advantage over Vettel, with Massa a further 3.7s back.

On the edge of the points-scoring positions, Sainz in P10 was coming under pressure from the Red Bulls of Ricciardo and Kvyat. The position would soon fall to Ricciardo as Sainz was hit with a five-second penalty for leaving the track and gaining an advantage when he passed Button. He immediately served the penalty, changed to a set of soft tyres and dropped to P18.

By the start of lap 18 Hamilton had effortlessly increased his lead over Vettel to almost 10 seconds, with Massa third ahead of Williams team-mate Bottas. Rosberg was the first of the front-runners to pit, diving in from fifth place to take on a set of medium tyres. Perez was sixth on the road ahead of Sauber’s Marcus Ericsson and Raikkonen in seventh.

Williams responded to Rosberg’s stop by pitting Massa, who also took on medium tyres. The undercut worked for Rosberg, though, and unable top match the Mercedes works driver’s pace, Massa dropped behind the German.

Bottas made his sole visit to the pit lane on lap 22 but the stop was a relatively slow 4.0s by the time the pit stop phase was over, both Williams cars had lost places to Rosberg.

Raikkonen was in third on old starting soft tyres but was passed on lap 28 by Rosberg and the Finn was the last of the frontrunners to pit, from fourth place, on lap 28. He rejoined in P10.

Kvyat had pitted from P9 but was on a different strategy to many of those ahead having start on medium tyres and on lap 27 he bolted on a set of quicker softs for his final stint. He rejoined in P12 behind Sainz.

Ricciardo was the last to make a first regulation pit stop and on lap 30 he visited the pit land from P7. Like Kyat, he shed his starting medium tyres and took soft tyres for a late-race charge.

With the stops complete, Hamilton held the lead on lap 33, 19.3s ahead of Vettel who was 5s clear of Rosberg. Massa was now fourth ahead of Bottas with Perez in sixth place. Raikkonen had climbed to seventh after passing Force India’s Nico Hulkenberg on the previous lap and the final points positions were occupied by Ericsson and Ricciardo, with Kvyat now 11^th.

The second half of the race unfolded in similar fashion to the opening phases of the race, with Hamilton stretching further ahead and with Vettel consolidating his second place ahead of Rosberg.

Rosberg was told by his team, however, that they expected Vettel’s tyres to deteriorate more rapidly than their own in the final stages and in the closing laps Rosberg began to reel the Ferrari man in.

The gap between the pair dropped to below three seconds but Vettel’s path to the flag was made more comfortable when Rosberg’s engine, an older Spa-specification unit he had been forced to use due to a problem with his Monza engine in practice, expired with two laps to go.

Ahead Hamilton was being given the order to increase his pace and he eventually took the flag 25 seconds ahead of Vettel. Behind them Massa fought a nip and tuck battle with team-mate Bottas for the final podium place and the duo crossed the line just inches apart, with the Brazilian to the fore. Behind them Sergio Perez was sixth for Force India, while team-mate Nico Hulkenberg took seventh. Red Bull Racing’s put in a battling drive to climb from 19^th place on the grid to take eighth place and the final points positions were occupied by Sauber’s Marcus Ericsson and the second Red Bull of Daniil Kvyat.

2015 Italian Grand Prix – Race
1 Lewis Hamilton Mercedes 1:18:00.688 53
2 Sebastian Vettel Ferrari +0:25.042 53
3 Felipe Massa Williams +0:47.635 53
4 Valtteri Bottas Williams +0:47.996 53
5 Kimi Raikkonen Ferrari +1:08.860 53
6 Sergio Perez Force India +1:12.783 53
7 Nico Hulkenberg Force India +1 Lap 52
8 Daniel Ricciardo Red Bull Racing +1 Lap 52
9 Marcus Ericsson Sauber +1 Lap 52
10 Daniil Kvyat Red Bull Racing +1 Lap 52
11 Carlos Sainz Toro Rosso +1 Lap 52
12 Max Verstappen Toro Rosso +1 Lap 52
13 Felipe Nasr Sauber +1 Lap 52
14 Jenson Button McLaren +1 Lap 52
15 Will Stevens Manor +2 Laps 51
16 Roberto Merhi Manor +2 Laps 51
17 Nico Rosberg Mercedes +3 Laps 50
18 Fernando Alonso McLaren +6 Laps 47
19 Pastor Maldonado Lotus 
20 Romain Grosjean Lotus