This year's Monaco Grand Prix has given rise to a big question: Why are teams allowed to change tyres during race suspensions?

Red Bull Racing's Sebastian Vettel had a good start to race weekend at Monaco. After qualifying on pole position, he came under massive pressure while conserving his tyres from Ferrari’s Fernando Alonso and Mclaren's Jenson Button.

The event had started well, with Vettel leading confidently from Button and Alonso. Then Button pitted on lap 15, Vettel on 16 and Alonso on 17. However, the flow of the race was interrupted when Massa, having just been passed by Hamilton for 10th place, crashed in the tunnel after veering off line. At the same time Michael Schumacher’s Mercedes had ground to a fiery halt at Rascasse.

When the race resumed, Alonso slowly ate away at Vettel’s lead, together with Button until an incident happened on lap 67 that blew the race. Under pressure from an overtaking Pastor Maldonado in the Williams, Sutil went wide at Tabac and hit the wall in the Swimming Pool with his right rear wheel. As the Force India then ran wide in the second section of the Pool, a lapped Alguersuari ran over the kerb and launched himself into the back of Hamilton, who’d just passed Maldonado, smashing the McLaren’s rear wing and inadvertently then forcing an innocent Petrov into the wall with a heavy impact.

The incident happened as the leaders were threading their way through the back markers, but the race was soon suspended as it became apparent that the Russian was unconscious and needed medical assistance. As the decision was taken to suspend the race, everyone went for the freshest tyres they had. When the race resumed for its final six laps, McLaren repaired Lewis Hamilton’s rear wing and Vettel, back on badly-needed fresh rubber, won easily from Alonso and Button.

Hamilton had an awful afternoon filled with penalties and added times. He dropped to 10th at the start, using soft tyres, pulled a brilliant pass on Schumacher at Ste Devote on the 10th lap, then passed Felipe Massa for 10th at the hairpin on lap 34, though they touched. That earned him a drive-through penalty. He collided with Maldonado at the restart on lap 74, which resulted in 20 seconds added to his race time for causing the collision.