Nick Dunlap will take a three-shot lead into the final round of The American Express tournament as he chases the first win by an amateur on the PGA Tour for 33 years.

The University of Alabama student shot 10 birdies and an eagle in a third round 60 – equalling the lowest round by an amateur in a tour event – on the La Quinta course to follow his second round 61 as he moved into pole position on 27-under-par.

Phil Mickelson was the last amateur to win on the PGA Tour in 1991.

Overnight leader Sam Burns is three shots back after a 65 at the Stadium Course, one of three used for the tournament and the site of the final round, where Justin Thomas equalled the course record with a 61 to sit a further stroke back.

South Africa’s Christiaan Bezuidenhout is the only other player within six shots of the lead.

Playing as a sponsor’s invite, Dunlap is the first amateur to make the cut at the event and while he will not collect the 1.5million dollars (£1.18million) prize money, a win would secure his PGA Tour card for two years.