Updated

Nico Rosberg kept his cool amid the chaos to win the crash-marred Monaco Grand Prix on Sunday and give Mercedes its first victory of the season.

The German driver began from pole position for the third straight GP, but he had to re-start three times after the race was held up by a safety car, a red flag and the safety car again.

Rosberg finished ahead of championship leader Sebastian Vettel and his Red Bull teammate Mark Webber. Lewis Hamilton finished fourth.

The red flag came out with about 30 laps to go when Williams driver Pastor Maldonado was nudged into the wall by Marussia's Max Chilton.

Earlier, Ferrari's Felipe Massa crashed and the safety car came out a second time when Frenchman Romain Grosjean smashed into Daniel Ricciardo.