Padraig Harrington shot six birdies and two bogeys to lie eight points off the lead after the opening round of the Barracuda Championship in Reno.
Harrington opened his round with a bogey five to go to minus one point, but birdied the second, fourth and sixth to lie on five points at the turn.
Birdies at 10 and 11 added four more points, and although he dropped a point with a bogey five on the 15th, Harrington finished well with two points for a birdie on the last.
American Nick Watney made nine birdies in a bogey-free round as he took an early lead at the event, which uses the modified stableford format to allocate points based on the number of strokes taken at each hole.
Watney racked up 18 points with his stellar first round to take the initiative in the tournament.
Watney managed four birdies on the front nine, before things got even better for him as he picked up shots at the 10th, 13th, 14th, 15th and 18th holes.
"I'm very pleased with the way I played today," Watney told www.pgatour.com.
"This is pretty close to home. So it's nice to see a lot of friends and family. I'm enjoying myself and hope it continues like this."
His nearest challengers in Nevada are Australian Geoff Ogilvy and New Zealander Tim Wilkinson, who both finished two points behind on 16 after the opening day.
It could have been even better for Wilkinson though, who also managed to rack up nine birdies and would have been level with Watney were it not for bogeys on the second and sixth holes.
Ogilvy, meanwhile, managed to pick up eight birdies to put himself in a strong position.
The 2006 US Open winner told www.pgatour.com: "It was there for the taking. I birdied the holes I was supposed to."