Respective team mates Valtteri Bottas and Kimi Raikkonen confirmed just how close qualifying will be, as the Finnish duo took third and fourth, both within just three-tenths of Hamilton’s benchmark lap time.
Mercedes had their cars honed a little better than yesterday and Bottas was certainly happier with his set-up, while Vettel had a new chassis in is Ferrari, and was also better hooked up.
In the end, as all of the top four ran Pirelli’s ultrasoft tyres, it was Hamilton who made it a grand slam of all three sessions, with a lap of 1m 34.478s which only slightly better his FP2 time.
Vettel, however, was only 0.092s adrift with 1m 34.570s, as Bottas posted 1m 34.692s and Raikkonen 1m 34.755s.
On that form, qualifying may well come down to who can get the cleanest lap.
Behind the leading quartet, Max Verstappen’s Red Bull was left a little breathless as the Dutchman struggled to 1m 35.103s for fifth, but that was better than team mate Daniel Ricciardo managed, as a late improvement yielded on 1m 35.723s after a slight off-course excursion cost him time. He ended up in ninth place, and there’s more bad news for the Milton Keynes team; as expected, with a sixth engine and a sixth MGU-H of the season, Verstappen will get a 15-place grid drop.
Felipe Massa continued Williams’ sudden upturn in performance to take sixth on 1m 35.346s, as Nico Hulkenberg and Carlos Sainz jumped up to seventh and eighth on 1m 35.608s and 1m 35.650s respectively for Renault. That pushed the Force Indias down to 10th and 11th, with Sergio Perez on 1m 35.802s from Esteban Ocon’s 1m 35.965s.
Further back, rookie Brendan Hartley was 15th on 1m 36.818s, but Toro Rosso team mate Daniil Kvyat was in trouble with a car issue and finished 20th, one place behind Haas’s Romain Grosjean who blotted his homework with a terminal spin partway through.
The scene is now set for what may be the closest qualifying session so far this season, which will start two hours later than normal at 1600 local time and which will be followed by a Justin Timberlake concert for race fans.
WATCH: FP3 action from the USA
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