Phil Mickelson still feels as young as ever. He still plays that way, too.
Mickelson began his 27th full season as a pro Thursday by flirting with one of the few feats he hasn’t accomplished — golf’s magic number. The 48-year-old lefthander still shot a 12-under-par 60 in the Desert Classic, tying his career-low score he last shot in the Phoenix Open six years ago. It was the most under par he has been in any of the 2,077 rounds he has played on the PGA Tour.
‘‘It was a kind of a lucky day for me in the sense that I did not feel sharp heading in,’’ Mickelson said. ‘‘I haven’t really had the intense practice sessions that I would like, but I felt like all parts were OK and it just clicked. “Some days you have those days where it just clicked. And the bad shots that I hit, I got away with. I was able to kind of not have the big score.’’
Needing to play the final two holes in 2 under to shoot 59 on the foggy, rainy day at La Quinta Country Club, Mickelson missed a 15-foot birdie try on the par-4 17th before holing a 9-footer for birdie on the par-4 18th.
The Desert Classic is the only PGA Tour event to yield two sub-60 rounds. David Duval had a 59 at PGA West’s Palmer Course when he won in 1999. Adam Hadwin shot 59 at La Quinta in 2017.
‘‘I was aware of it,’’ Mickelson said. ‘‘I was giving it all I had and I had a good chance.’’
Mickelson had a three-stroke lead over Adam Long, the 31-year-old PGA Tour rookie who finished off a 63 in the dark on PGA West’s Nicklaus Tournament Course.
The fog-delayed round was Mickelson’s first on tour since early October and the first in competition since beating Tiger Woods in Las Vegas in November in a made-for-TV event.
‘‘That was an interesting shot because I could have easily lost one and I ended up picking one up,’’ he said.
The tournament winner in 2002 and 2004, Mickelson will play the Nicklaus Course on Friday and PGA West’s adjacent Stadium Course — also the site of the final round — on Saturday.
He won the World Golf Championships-Mexico Championship last year for his 43rd PGA Tour title and first since the 2013 British Open.
Long eagled the par-5 fourth and had seven birdies — five in a row from Nos. 9-13 — in an eight-hole stretch.
LPGA — No one was entirely sure what to expect from the first LPGA Tour event of the year — least of all Stacy Lewis.
Nearly three months after Lewis became a mother, and six months after she last played on tour, she opened with seven birdies for a 5-under 66 that left her one shot behind Brooke Henderson and Eun-Hee Ji at the Diamond Resorts Tournament of Champions at Lake Buena Vista, Fla.
Henderson overcame a slow start with a bogey on the second hole and a par save on No. 3 at the Tranquilo Golf Club at Four Seasons. She birdied five of her last eight holes for a 65 to tie Ji. , who had a bogey-free round.
The event had the feel of a pro-am because of all the celebrities and athletes, although it wasn’t all hits and giggles. Along with the 26-player field from the LPGA Tour competing for a $1.2 million purse, 49 entertainers are competing for a $500,000 prize fund using the modified Stableford scoring system.
Tennis player Mardy Fish led that field with 39 points for a two-point lead over a group that included retired pitcher Mark Mulder.
But it was a different vibe from most LPGA events.
‘‘I had to remind myself it wasn’t Wednesday afternoon, it was Thursday, and I had to get a good score together,’’ Henderson said. ‘‘I think that’s when things kicked in on the front nine. I started getting a couple of birdies to recover from that bogey, and then from there I was ready to go and made a lot of birdies.’’
Lydia Ko joined Lewis at 66. Both formerly were No. 1 in the world.
Another shot back were Jutanugarn, Lexi Thompson and Mirim Lee.
Jutanugarn started the year with a new caddie, who previously worked for his fiancee, ANA Inspiration winner Pernilla Lindeberg. She opened with a 77, the highest score among LPGA players.
The Thai said she had some nerves from not having played in two months. And not being used to celebrities in her group also required an adjustment.
‘‘Because I didn’t play for so long — especially playing with them — I feel upset. He hit like 60 yards past me,’’ said Jutanugarn, who played in the same group with retired baseball players Josh Beckett and Kevin Millar. ‘‘Every hole he has a chance to make eagle, so I thought, ‘Maybe I'm not that good.'’’
She was referring to Beckett on the long tee shots. She didn’t know much about either, though she figured one thing one quickly.
‘‘I know they are baseball players. I know both of them are really famous,’’ she said. ‘‘And nobody asked me for an autograph. They all asked them.’’
Lewis had not played on the LPGA Tour since a 66 to tie for 39th on July 12 at the Marathon Classic in Ohio. She gave birth to her first child, a daughter they named Chesnee, on Oct. 25.
The biggest difference was her routine.
She now has to remember where to find daycare, to get out the door a little earlier and making sure she has all the bags for her game and her daughter.
‘‘You've got to take three trips to the care to get out the door every morning,’’ she said. ‘‘So it’s a new normal.’’
Her game looked like the old Stacy Lewis, at least for the opening round. She was 1 under at the turn until rolling in five birdies to offset one bogey on the back nine.
European — Shane Lowry recovered from two early bogeys by hitting enough good shots for a 2-under 70, giving him a one-shot lead going into the weekend at the Abu Dhabi Championship.
Three-time major champion Brooks Koepka, who has a chance to return to No. 1 in the world this week, bogeyed the 18th hole for a 70 and was five shots behind. Dustin Johnson had a 71 and was eight shots behind.
Another shot back was Tommy Fleetwood, who is going for a third straight title in Abu Dhabi.