Monaco GP: Vettel tops final practice, Button given penalty

Four-time world champion Sebastian Vettel on Saturday dominated the final practice at the Monaco Grand Prix.

Vettel was 0.345 seconds ahead of Ferrari team mate Kimi Raikkonen. Vettel's title rival and three-time world champion Lewis Hamilton was fifth fastest in the second Mercedes, followed by Red Bull's Daniel Ricciardo, in a session in which Toro Rosso and Haas also starred.

Meanwhile, Jenson Button, who was the 12th fastest on his one-off return to Formula 1, is set to start last for what could be his final Formula One race after being hit with a 15-place grid penalty at the practice session.

Button received a 15-place grid penalty after McLaren were forced to make unscheduled power unit changes to the British driver's car.

"It's awful for Jenson and awful for McLaren," formula1.com quoted racing director Eric Boullier as saying. "And not expected at all. But it's Monaco, so we'll try anything we can.