Down to his last chance to earn a US PGA Tour card and an all-too-honest Ashley Hall almost let it go in the opening round of the Web.com Tour Championship in Florida.

The Australian called a penalty on himself when he noticed his ball slightly move on the Valley Course at the TPC Sawgress on Thursday, but went on to finish the day with a one-shot lead over Sweden’s Robert Karlsson and American Mark Anderson.

The 29-year-old birdied two of his last three holes for an impressive seven-under-par 63 – his second-best score of the year.

“I put it on a good lie and the Bermuda grass wasn’t strong enough,” he said. “I could tell as soon as I put my club on the ground that I moved the ball.”

Hall has never had a PGA Tour card and would need a top finish at Sawgrass this week to earn one for 2013-2014.

The event is the last of four tournaments for 25 players to earn PGA Tour cards based on a money list from those events.

The Australian has missed the cut in the past three tournaments, as well as last month’s final regular-season event by just $US1922 ($A2063).

Ten other Australians need a result this week to book a spot on the 2014 Tour, including Alistair Presnell, Mathew Goggin, Aron Price, Nick Flanagan and Rod Pampling.

Scott Gardiner, who is almost certain to earn his card, hit a three-under 67 for a share of 15th.

He sits ahead of Goggin, Presnell, Price and Flanagan all on one-under 69.

Pampling is back in a tie for 55th after shooting an even-par 70.