Fowler one back of co-leaders Blair, Murray at The American Express

LA QUINTA, Calif. (AP) -- Rickie Fowler, playing in The American Express for the first time in six years, carded a 7-under 65 Thursday to sit one stroke off the lead shared by Zac Blair and Grayson Murray.

"It's a good start," Fowler said. "Obviously you look at scores it's usually pretty low out here, especially when you look at weather like this and the conditions of the courses. Conditions are perfect here at La Quinta. Greens are about the best that we see all year."

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Fowler, Scottie Scheffler and Hank Lebioda shot 65. Fowler and Scheffler opened at La Quinta, while Lebioda played PGA West's Jack Nicklaus Tournament Course.

Murray and Blair shot 64 in sunny and mostly calm conditions. Murray made nine birdies on the day, tying his career-best in a round, on PGA West's Stadium Course, also the site of the final round in the pro-am event.

"I've been here since Dec. 30 working on the game and I feel like I probably am the most prepared of the field for all three courses," said Murray, the 2017 Barbasol Championship winner. "Coming off of a long offseason you never expect to come out the gates like I did firing, but I'm comfortable around all three of these courses. ... I love it out here in the desert."

Blair had a bogey-free round at La Quinta Country Club.

"It was perfect today, course was in really good shape," Blair said. "Drove it really well, made some good putts. But it's a little easier out here this week right now than it was in Hawaii last week, so it's nice."

Phil Mickelson struggled off the tee in his first round of the year, shooting a 2-under 70 to fall six strokes behind Blair and Murray.

"I didn't score as I probably could have or wanted to, but I really had a good day," said Mickelson, the 49-year-old Hall of Famer competing for the first time since early November. "It wasn't quite as sharp as I wanted it to be, maybe a little bit rusty, but it was a good first day."

Mickelson, also the tournament host, birdied the par-5 fifth and sixth holes to get to 3 under, then gave away two strokes on the par-4 eighth when he drove left into the water and hit his third left of the green.

"I've been working on kind of a little low shot to get it in play and I hit it a few times today and I didn't hit it as efficiently as I wanted to, but the miss wasn't as bad as some of my other drives," said Mickelson, the tournament winner in 2002 and 2004.

Mickelson hit so far left on the par-4 ninth that he was in the rough on the far side of the adjacent first fairway. It wasn't that bad of a shot, though, because he was trying to hit into the first fairway to give himself a better angle at the back right pin.

"Takes the water out of play and I just have a much better angle," Mickelson said. "I actually pushed it a little bit across and got a little bit unlucky to be behind the tree, but I ended up just chipping a little wedge underneath it and getting it on."

The Hall of Famer made a tap-in par there, and birdied the par-5 11th and 13th, holing out from the rough on 13 after failing to reach the green from a left bunker. He made bogey on the par-4 17th, missing a 7-footer after hitting left into a bunker.

"I feel like I'm ready to go on a tear, like I'm excited to play," Mickelson said. "Felt like 70 was the worst I could have shot, I'm going to come out tomorrow and get it going."

Playing partner Tony Finau shot 69.

Mickelson and Finau will play the Nicklaus Tournament Course on Friday, then the adjacacent Stadium Course on Saturday.

Defending champion Adam Long opened with a 69 at La Quinta.