The last 12 months on the golf course have been interesting ones for Phil Mickelson.

The Hall of Famer capped a torrid West Coast swing in 2018 with a win in the WGC-Mexico Championship, snapping a nearly five-year winless streak with his 43rd PGA Tour win.

But the rest of the year was a mixed bag for the 48-year-old Mickelson, with just one more top-10 finish, a rules controversy at the U.S. Open, a missed cut at the PGA Championship, a disappointing shutout at the Ryder Cup and a victory in The Match, where he outlasted Tiger Woods in a $9 million winner-take-all payday.

Thursday, on a rare soggy day in the Coachella Valley, Mickelson showed he is still more than capable of brilliant and thrilling golf. In his first start in 2019, Mickelson scorched La Quinta Country Club for a 12-under 60 and the first-round lead in the Desert Classic.

The round ties the record for lowest opening score in the 60-year history of the desert’s PGA Tour event, set by Pat Perez in 2006.

It is also Mickelson’s third 60 on the tour, matching rounds in 2005 and 2013 at the Waste Management Open. Mickelson is the first player in PGA Tour history with three rounds of 60 or better, though he has never shot 59.

“I really didn't think that this was going to be a day that I was going to go low. I came in with very low expectations,” Mickelson said. “I haven't had a lot of time to practice and prepare and I felt like all areas were okay, but you never really know until you get out and you play and compete.”

Mickelson said he figured out early in the round he had something special for the galleries that waited out an hour-long fog delay to watch him play.

“I hit a shot here or there and ended up making a putt and all of a sudden I was quite a few under par,” he said. “The good thing was I made a couple bad swings and I got away with them. This golf course, there's out of bounds close by, it's easy to make big mistakes and I was able to get away with the one or two poor swings. And then I putted phenomenal.”

Mickelson's round was the best of a low-scoring day at the tournament that was delayed one hour by heavy fog in the La Quinta area. Adam Long fired a 63 on the Nicklaus Tournament Course at PGA West to hold second place alone, while Curtis Luck shot 64 at La Quinta. Four players are tied at 64.

Defending champion Jon Rahm shot 66 at La Quinta, while world No. 1 Justin Rose shot 68 on the same course.

Having shot 60 twice before on tour, and being on a course where Adam Hadwin shot 59 just two years ago, Mickelson was more than aware of the growing 59 excitement.

“Certainly on 16, I was aware that if I make that 4-footer for birdie and then birdied the last two I would shoot 59. I was aware of it, I was giving it all I had, and I had a good chance,” he said. “On 17 I hit a nice tee shot in a good spot to kind of hook a sand wedge into that back right pin for me. And I hit a good shot, I had 18 feet though, I should have hit that closer, but still had a good chance to make the putt.”

Mickelson missed the putt, but then made a 10-foot birdie on the final hole for the 60.

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Mickelson’s round started with two birdies followed by two pars. He then took advantage of the course’s short back-to-back par-5s for birdie on the fifth and an eagle on the sixth. Three consecutive birdies started at the ninth and pushed him to eight under, and a birdie on the par-4 12th pushed him to nine under, including five under on the four par-5s.

When Mickelson chipped in for a birdie on the tough par-4 14th, a 59 seemed possible.

Mickelson admits that 2018 was a strange year for him, but he’s not worried about it now.

“Those were all last year. That was all 2018,” he said. “So we're starting fresh and right now, it's a good start to the year. So this is, it's been a fun round."

Mickelson’s 60 might even change his schedule for the next few weeks. At 48 and looking to cut back on his schedule, Mickelson has not officially committed to the Farmers Insurance Open in his hometown of San Diego next week. That might change now.

“Honestly, I just wasn't sure I would be ready for a golf course that long and hard. And so I've been kind of waiting to see how my game felt the first couple of days,” Mickelson said. “(Torrey Pines) is one of the hardest courses we play. It's 7,600 yards, fairways are tight, there's a lot of rough and it's, unless I'm playing my absolute best, that's not really a great place for me.”

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Mickelson is looking to win in the desert for the third time. He won in 2002 and 2004, making him one of seven players to win the desert tournament twice. Arnold Palmer won the event five times.

Rahm, the defending champion of the tournament who opened with a 62 at La Quinta last year, said he’s not surprised that older players like Mickelson can still post great scores on tour, especially in events like the Desert Classic.

“Phil is 48 and was able to win last year,” Rahm said. “I just played with him a couple days ago, and he's swinging the club as fast as he's ever swung it so it's not like he's going down on strength.”