Jochen Rindt won the US Grand Prix at Watkins Glen, ending five years of chasing a victory, underlining the speed of the Lotus even if Rindt himself continued to have reservations as to its safety. Piers Courage took second in what was generally considered to be his best grand prix.
The race was overshadowed by a serious accident involving Graham Hill when his Lotus suffered a high-speed puncture. He had been struggling throughout with handling issues when he spun on the 90th lap. As he got back in the car after checking for damage he noticed his rear tyres were bald. Importantly, Hill was unable to belt himself back in properly (he needed the help of mechanics) and as he passed the pits he indicated he would be coming in for new tyres.
Seconds later one of the tyres collapsed, the car flipped and Hill was hurled from the Lotus. He suffered major leg injuries, and in hospital suffered complications. He was advised he would never race again - he was back in time for the following season.
Rindt dominated qualifying and led the race throughout, as well as setting the fastest lap, while Courage, in a privately-entered Brabham frustrated Jacky Ickx and Jack Brabham until Ickx's engine blew, and then near the end Brabham's car ran out of fuel, his team's consumption calculations thrown out by the pace of the race.
For the second grand prix in succession, Stewart, already crowned champion, failed to finish, his early battle with Rindt ended by an oil leak.