JB Holmes, competing in only his fourth PGA Tour event since having brain surgery, gave himself a major boost by charging into contention at the Northern Trust Open in Thursday.
The big-hitting American birdied four of his first five holes, and three of his last four, to card a four-under-par 67 in the opening round at sunny but wind-buffeted Riviera Country Club.
Having made just one cut in three starts on the 2012 PGA Tour, Holmes put himself in position to challenge for a third victory on the US circuit with his best score of the season.
"Overall it was a really good day for me," the 29-year-old from Kentucky said after mixing eight birdies with two bogeys and one double-bogey. "We got about four holes where the wind wasn't blowing, so it was whipping most of the day on us.
"Coming in (on his back nine) I made some bogeys, a couple of them were bad breaks and a couple of them I just hit a bad shot.
"But overall I hit the ball pretty good," said Holmes, who ended the first round a stroke behind leader Phil Mickelson.
"My mindset was really good all day, I made a bunch of birdies and putted pretty good."
Swirling winds gusted up to 35 mph (56 kph) across the iconic Riviera layout and Holmes felt he had been fortunate to start his round at the driveable par-four 10th.
"On 10 you have to deal with the crosswind, and on 11," he said after recording birdies at the 10th, 11th, 12th and 14th. "After that it's downwind for a few holes, so you have a chance to make some birdies there.
"It was nice to get off to that kind of start. I really hit some good shots and made some good putts. I really enjoy playing here. I like the layout of this golf course and felt like I could shoot a pretty good score today."
Holmes returned to competition at last month's Farmers Insurance Open in San Diego, having been sidelined since August after being diagnosed with Chiari malformation, structural defects in the part of the brain which controls balance.
He had been experiencing vertigo-like symptoms since the Players Championship in May and pulled out of the Barclays Classic in August before having the condition diagnosed and then treated the following month.
Overall, though, he believes his game has been steadily improving.