Sebastian Vettel set the fastest time of final practice for the Singapore Grand Prix as Mercedes looked in genuine trouble.
After Mercedes claimed it was facing a real threat from Ferrari and Red Bull following Friday's running, FP3 appeared to back up its concern as Vettel went nearly half a second clear of the field on the supersoft tyre. Team-mate Kimi Raikkonen made it a Ferrari one-two as Red Bull emerged as its closest challenger.
Daniil Kvyat was third - 0.035s slower than Raikkonen - while Daniel Ricciardo was fourth in the second Red Bull, 0.677s off the pace. When the Mercedes pair attempted supersoft laps, the deficit was surprising as championship leader Lewis Hamilton could only set the fifth fastest time but was over 1.1s slower than Vettel.
Hamilton also made an error at Turn 7, locking up and taking to the escape road before spinning his car round and rejoining. Later in the session, Hamilton was pushing for another timed lap on supersofts - but not showing a marked improvement - when he came across a Toro Rosso at the hairpin and locked up to avoid running in to the back of the car ahead, raising his hands in frustration.
Nico Rosberg was sixth in the second Mercedes, ending the session 1.5s adrift and only 0.014s ahead of Fernando Alonso in the McLaren-Honda. Mercedes even took to Twitter to state: "There is no hiding the potential here... the pace of our rivals is genuine and very quick!"
Carlos Sainz and Max Verstappen were eighth and ninth quickest respectively for Toro Rosso despite both drivers going off at Turn 7, while Marcus Ericsson rounded out the top ten.
The fight for Q3 in qualifying looks set to be a close on, with 0.6s separating Rosberg in sixth place with Pastor Maldonado in 16th. Williams is in the middle of that group but will be worried after being unable to get either driver in to the top ten.
The two Manor drivers were again comfortably off the pace as they focused on long runs having missed out on race simulations when both Alexander Rossi and Will Stevens crashed on Friday. Rossi was almost seven seconds off the pace ahead of his first qualifying session, while Stevens didn't complete a low fuel lap.
AS IT HAPPENED: Singapore Grand Prix FP3
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| Pos | Driver | Team | Time | Laps |
|---|---|---|---|---|
| 01 | Sebastian Vettel | Ferrari | 1:45.682 | 12 |
| 02 | Kimi Raikkonen | Ferrari | 1:46.132 | 12 |
| 03 | Daniil Kvyat | Red Bull | 1:46.167 | 19 |
| 04 | Daniel Ricciardo | Red Bull | 1:46.359 | 14 |
| 05 | Lewis Hamilton | Mercedes | 1:46.802 | 15 |
| 06 | Nico Rosberg | Mercedes | 1:47.223 | 16 |
| 07 | Fernando Alonso | McLaren | 1:47.237 | 14 |
| 08 | Carlos Sainz | Toro Rosso | 1:47.301 | 18 |
| 09 | Max Verstappen | Toro Rosso | 1:47.464 | 17 |
| 10 | Marcus Ericsson | Sauber | 1:47.568 | 20 |
| 11 | Valtteri Bottas | Williams | 1:47.587 | 20 |
| 12 | Nico Hulkenberg | Force India | 1:47.640 | 16 |
| 13 | Jenson Button | McLaren | 1:47.715 | 14 |
| 14 | Felipe Massa | Williams | 1:47.733 | 21 |
| 15 | Pastor Maldonado | Lotus | 1:47.817 | 16 |
| 16 | Sergio Perez | Force India | 1:48.002 | 15 |
| 17 | Romain Grosjean | Lotus | 1:48.116 | 15 |
| 18 | Felipe Nasr | Sauber | 1:48.932 | 20 |
| 19 | Alexander Rossi | Manor | 1:52.588 | 26 |
| 20 | Will Stevens | Manor | 1:55.293 | 22 |
