Vettel increased his Championship advantage by winning a chaotic Monaco Grand Prix that was restarted with only six laps to go following a red flag for a crash involving Vitaly Petrov at the Swimming Pool. The Red Bull driver had opted against pitting during a mid-race safety car period, and ran a 56-lap stint on super soft rubber against all expectations, gaining track position over previous leader Jenson Button. That left him ahead when the race was red-flagged, at which point he, second placed Fernando Alonso and Button, who had dropped to third after pitting just before a mid-race safety car, were all allowed to fit new tyres. His eventual winning margin was 1.1 seconds ahead of Alonso, who was a similar distance clear of Button. The race boiled down to a six-lap sprint following a red flag for a crash involving Petrov, Jaime Alguersuari and Lewis Hamilton, that was triggered by Pastor Maldonado passing Adrian Sutil for sixth place at Tabac. The one-stopping Sutil, who had ran fourth for a long time but was dropping back on old tyres, smacked the wall exiting the corner and punctured his right-rear tyre. While trying to avoid the slowing Force India, Petrov ran into the back of Alguersuari's Toro Rosso, which in turn hit the rear of Hamilton's McLaren. Alguersuari and Petrov hit the wall hard, forcing the race to be stopped with six laps to go and necessitating Petrov's extrication from the car by medical staff. Prior to the red flag, the street circuit was staging the best race of the year. Having lost the lead to Button thanks to a sluggish opening pitstop on lap 16, Vettel opted against pitting when Felipe Massa's mid-race crash brought out the safety car. Button, who had already stopped twice by this point, was clearly the faster driver on his fresher rubber, but had also lost track position to Alonso during the safety car period. Button made a third stop on lap 48 after becoming stuck behind Vettel, but reduced an 18-second deficit to less than a second with eight laps to go. His problem, however, was that Alonso's Ferrari was in between them. Button's hopes of victory rested with Vettel's and Alonso's tyres going off before his, as both switched their strategies and opted against making further stops. The stoppage and subsequent tyre changes put paid to that, however. Mark Webber finished fourth, having dropped as low as 14th early on due to a 15-second stop as Red Bull pitted him on the same lap as Vettel. His two-stop strategy left him with fresher rubber than many of the cars around him during the second half of the race, allowing him to pass Kamui Kobayashi's Sauber, Sutil, Petrov and Maldonado within the final 15 laps. Kobayashi ceded fourth to Webber after missing the chicane with two laps to go, but still collected the best result of his career. Maldonado kept up his status as a Monaco expert and looked like finishing sixth, but he crashed out of the race at Ste. Devote with five laps to go after contact with Lewis Hamilton. Hamilton's rear wing was damaged in the Petrov/Alguersuari accident, and took seventh after the McLaren mechanics fixed the right support during the stoppage. The Briton's race was a frustrating one. Passed by Michael Schumacher's slow-starting Mercedes at the Loews hairpin on the opening lap, he lost a significant amount of time when the German's rear tyres dropped off at an alarming rate within the first 10 laps. Even after passing the seven-time world champion at Ste. Devote, his pace was compromised as he became bogged down in a seven-car battle for fourth place behind Sutil. He, Webber and Felipe Massa all came together at Loews on lap 34 - an incident that Hamilton was deemed to have caused and received a drive-through penalty for - but by that time Massa was out, the Ferrari driver having hit the wall in the tunnel as Hamilton passed seconds later. Hamilton eventually finished sixth, ahead of the lapped Sutil, Nick Heidfeld's Renault, Rubens Barrichello (Williams) and Sebastien Buemi (Toro Rosso). Paul di Resta finished 12th after receiving a drive-through penalty for the same reason as Hamilton . colliding with another car at Loews, but the Force India driver also damaged his car in the incident with Alguersuari and was force to pit for a new nose. Schumacher did not make the finish, his Mercedes grinding to a halt just ahead of Alonso as the safety car came out for the Massa crash. Timo Glock was the only other retiree, the Virgin driver's right-rear suspension failing just before half distance.