Sebastian Vettel fastest in Monaco Practice Three as Jenson Button handed grid penalty

Sebastian Vettel topped the timesheets again in Practice Three for the Monaco GP as Ferrari set a blistering pace around Monte Carlo's street circuit.

The championship leader's 1:12.395 improved the ultimate lap record he set on Thursday afternoon and saw him finish three tenths ahead of team-mate Kimi Raikkonen.

Mercedes improved their pace after struggling on Thursday but remained unable to challenge the Ferrari with Valtteri Bottas third, nearly half a second off Vettel's time, and Lewis Hamilton fifth, eight tenths down on his championship rival.

Max Verstappen's Red Bull split the two Silver Arrows.

"Ferrari are dominating and even the Red Bulls could upset or be threatening the Mercedes," Sky F1's Damon Hill said.

"We always wonder whether Mercedes are sandbagging. I think we'll see them back up again in Qualifying."

However, there was more woe for McLaren-Honda and Jenson Button as the Briton was handed a 15-place grid penalty on his racing return after Honda changed the MGU-H and turbo on his power unit.

Button finished 12th in the session with team-mate Stoffel Vandoorne, who faces a three-place penalty for his crash in Barcelona, 10th.

Daniel Ricciardo was sixth in the second Red Bull but four tenths slower than team-mate Verstappen and reported a brake-by-wire problem at the end of the session, stopping in the Ste Devote run-off area.

Toro Rosso continued their impressive weekend with both Carlos Sainz and Daniil Kvyat well within the top 10.

But Esteban Ocon's session was brought to a premature end when he crashed on the exit of the swimming pool and his Force India team face a big rebuilding job to ensure he can take part in Qualifying, which starts at 1pm.

Monaco GP Practice Three Timesheet
1. Sebastian Vettel, Ferrari, 1:12.395

2. Kimi Raikkonen, Ferrari, +0.345

3. Valtteri Bottas, Mercedes, +0.435

4. Max Verstappen, Red Bull, +0.545

5. Lewis Hamilton, Mercedes, +0.835

6. Daniel Ricciardo, Red Bull, +0.997

7, Carlos Sainz, Toro Rosso, +1.005

8. Daniil Kvyat, Toro Rosso, +1.168

9. Kevin Magnussen, Haas, +1.201

10. Stoffel Vandoorne, McLaren, +1.410

11. Sergio Perez, Force India, +1.541

12. Jenson Button, McLaren, +1.581

13. Esteban Ocon, Force India, +1.677

14. Felipe Massa, Williams, +1.677

15. Nico Hulkenberg, Renault, +1.888

16. Romain Grosjean, Haas, +2.152

17. Lance Stroll, Williams, +2.280

18. Jolyon Palmer, Renault, +2.769

19. Pascal Wehrlein, Sauber, +2.896

20. Marcus Ericsson, Sauber, +3.468

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