United States GP: 3rd & 4th for Williams in FP3

The final Saturday practice session for the Williams Martini team would see both Felipe Massa and Valtteri Bottas running and in the early part of the session Felipe would set the quickest time, 1m:39.820. Valtteri's first timed alp would see him fourth but his next lap would see him improve to be third with Ricciardo second, splitting the Williams pair. But Ricciardo would move ahead of Massa with a 1m:39.693 while for Valtteri he would set the fastest times in the first two sectors but would finish the lap in second with a 1m:39.798. With this the Williams team was second and third while in fourth was Alonso. But yet to set a time were both of the Mercedes cars but Hamilton would finally set a 1m:40.064 to be fourth. Rosberg was still in his pit having returned without setting a time with an issue with his car.

With twenty minutes remaining the order was Ricciardo from Valtteri, Felipe, Alonso, Hamilton, Kvyat, Grosjean, Raikkonen, Button, and Maldonado tenth. Rosberg would return to the track but would set a slow 1m:47.636. Hamilton had spun at Turn twelve while for Williams Valtteri had pitted. Both Williams drivers had yet to use the soft option tyre but with fifteen minutes of the session remaining the track would clear and it would be Alonso who would return running on the soft tyre with Rosberg following him out moments later. Rosberg was currently in second last place with Vettel slowest. But Vettel was focusing on race times having been forced to start the race from the pits due to exceeding his engine unit allocation. Valtteri was also out on the soft tyre along with Raikkonen.

Using the soft tyres Alonso was able to move to the top of the times with a 1m:39.108 as Rosberg pitted. Valtteri would start his quick lap and would set a 1m:38.437 to be 0.7 ahead of Alonso. Grosjean would improve to be fifth with Raikkonen now third just off his team-mates time. Felipe was also out on the soft tyre with just three cars still in their pits. Felipe was able to set a 1m:38.214 to move ahead of Valtteri and be quickest. But Hamilton would show that the Mercedes were the ones to catch setting a 1m:37.107 to be ahead of Felipe by 1.1 seconds. Sutil was now in sixth, 1m:39.000, to be behind Hulkenberg. With four minutes remaining the Williams team had their cars second and third but Rosberg was on a quicker lap having sorted out his issues. Ricciardo was now fifth but this would become sixth as Rosberg went second with a time of 1m:37.991. This was still 0.884 behind his team-mate Hamilton as both Williams drivers pitted.

It was reported that Rosberg's issue was a glazed brake disc. The Williams' pair stops would be brief with both returning to the track having carried out practice pit stops. Rosberg was on a better lap but still well off the pace set by Hamilton. With the end of the session Rosberg would fail to improve as the drivers returned back to their pits. So with the end of the session the order was Hamilton from Rosberg, Felipe, Valtteri, Alonso, Ricciardo, Hulkenberg, Sutil, Raikkonen, and Button in tenth. A very encouraging session for the Williams team but Felipe and Valtteri were over a second behind the quickest time.

Pos  Driver             Team		        Time     Laps
1 Lewis Hamilton 	Mercedes 		1:37.107 13 
2 Nico Rosberg 		Mercedes 		1:37.990 15 
3 Felipe Massa 		Williams-Mercedes 	1:38.214 19 
4 Valtteri Bottas 	Williams-Mercedes 	1:38.437 20 
5 Fernando Alonso 	Ferrari 		1:38.727 13 
6 Daniel Ricciardo 	Red Bull-Renault 	1:38.927 16 
7 Nico Hulkenberg 	Force India-Mercedes 	1:38.960 20 
8 Adrian Sutil 		Sauber-Ferrari 		1:39.000 22 
9 Kimi Räikkönen 	Ferrari 		1:39.143 17 
10 Jenson Button 	McLaren-Mercedes 	1:39.241 22 
11 Kevin Magnussen 	McLaren-Mercedes 	1:39.335 19 
12 Pastor Maldonado 	Lotus-Renault 		1:39.448 18 
13 Romain Grosjean 	Lotus-Renault 		1:39.561 21 
14 Sergio Perez 	Force India-Mercedes 	1:39.582 21 
15 Daniil Kvyat 	STR-Renault 		1:39.688 19 
16 Esteban Gutierrez 	Sauber-Ferrari 		1:40.208 22 
17 Jean-Eric Vergne 	STR-Renault 		1:41.443 12 
18 Sebastian Vettel 	Red Bull-Renault 	1:43.765 25