Lewis Hamilton secured his third world title with his tenth victory of 2015 during a thrilling topsy-turvy race at a wet/dry United States Grand Prix.
Hamilton inherited the lead during the closing stages when Mercedes team-mate Nico Rosberg went wide, though the German was able to hold onto second, keeping Sebastian Vettel at bay on the final lap.
Vettel had surged forwards from 13th place on the grid, completing the first lap in seventh place and picking off rivals thereafter.
On Intermediate tyres on a damp circuit, Hamilton had a better start than Rosberg but edged his rival wide at Turn 1, sending Rosberg into the run-off at the exit of the corner, with the pair making minor contact.
That dropped Rosberg down to fourth position, behind Daniil Kvyat and Daniel Ricciardo, as the Red Bull drivers swapped positions at Turn 1.
Hamilton was harried by Kvyat until the Virtual Safety Car was deployed for the amount of debris at Turn 1.
That was caused by Felipe Massa and Fernando Alonso making contact at the start, before Felipe Nasr damaged his front wing a lap later after hitting Sauber team-mate Marcus Ericsson.
Rosberg utilised the end of the Virtual Safety Car period to his advantage as he cruised past Ricciardo into Turn 3 before passing Kvyat along the back straight.
Kvyat tried to re-gain the position a few laps later at the final corner but went wide, dropping behind Ricciardo.
Ricciardo’s stay in third was brief as Rosberg ran too deep into Turn 1, allowing the Australian into second to close in on leader Hamilton.
As Hamilton tried to hold onto the lead, Ricciardo snuck up the inside into Turn 17 on lap 15 to snatch the advantage, moving ahead of the Mercedes driver.
Ricciardo rapidly pulled out a three second lead as Hamilton was challenged by Rosberg, narrowly defending his position at the end of the back straight.
Rosberg tried again a couple of laps later and was successful in his attempt, with Hamilton diving into the pits for slicks.
The other leading trio came in a lap later and demoted Hamilton to fourth position, though Ricciardo lost time when he went off at Turn 7, losing three seconds to Rosberg.
That allowed Rosberg to close in and he breezed past the Australian along the back straight soon after to take the lead, as Hamilton pulled a similar move on Kvyat.
Hamilton rapidly caught Ricciardo and cruised past on the back straight, by which time Rosberg was pulling clear at a rate of over two seconds a lap, building an advantage of 12 seconds.
However, Rosberg’s lead was wiped out soon after as Marcus Ericsson’s Sauber stopped entering the back straight, causing the deployment of the Safety Car.
Rosberg bolted away from Hamilton at the restart as the pair pulled clear of Ricciardo, though the Red Bull drivers began to struggle for pace.
Vettel picked off Kvyat with ease and soon got by Ricciardo, as the Red Bulls started to slip down the order.
Ricciardo fell into the clutches of Nico Hülkenberg, who appeared to have a slightly damaged front wing, and the German hit the Red Bull driver, causing terminal damage to his car.
Hülkenberg pulled off the circuit but the position of his car required the Virtual Safety Car once more, during which Rosberg took the opportunity to pit, emerging in fourth place, behind Vettel and Max Verstappen.
That left Hamilton in the lead on used Options, five seconds ahead of Vettel on semi-worn Primes, with Rosberg on fresh Options a few seconds further back.
Rosberg rapidly got by on Verstappen and closed in on Vettel, moving into second position, as Hamilton struggled up front on used Option tyres.
The Safety Car was deployed once more when Kvyat lost control of his RB11 exiting the penultimate corner, crashing into the barriers on the inside of the corner.
Hamilton and Vettel both stopped behind the Safety Car, the Briton dropping back into second and Vettel fourth, behind Verstappen.
Rosberg edged away from Hamilton at the restart as Vettel got by on Verstappen to elevate himself back into third.
However, Rosberg made a mistake on the approach to Turn 16 and speared off the circuit, promoting Hamilton into the lead.
Vettel closed in on Rosberg during the last few laps but the Mercedes driver hung onto second, enabling winner Hamilton to take his third crown.
Verstappen put in a starring drive to equal his highest Formula 1 result with fourth place, while Sergio Pérez claimed fifth as Jenson Button brought home points for McLaren in sixth.
Carlos Sainz Jr. was seventh, while Pastor Maldonado, Felipe Nasr and Ricciardo rounded out the top 10, the Australian moving ahead of Alonso on the last lap after the McLaren driver reported a lack of power. Alexander Rossi stayed out of trouble and was 12th for Manor Marussia.
Kimi Räikkönen spent the early stages battling with the Toro Rosso drivers before he went off at Turn 7 soon after changing for slicks.
Räikkönen was initially wedged into the barriers but he managed to get back on track, before being told to retire due to overheating brakes.
Neither Williams driver finished while Romain Grosjean and Will Stevens both sustained damage at the start and retired.