The 26-year-old, who finished in top 20 in the 2020 edition in September after impressive final rounds of 68 and 69, continued where she left off by carding a five-under-par 67 at Mission Hills Country Club in Rancho Mirage.
That left her in a tie for second place alongside China’s Shanshan Feng, the pair sitting a shot behind Thailand’s Patty Tavatanakit.
“I came here for the first time as an amateur when I was still in college, and it's just a fun place to be,” said Maguire, who has Scot Gary Marshall on her bag.
“Great golf course. It's a really good test. You got to drive the ball well. Hit your irons in the right places. And then there are lots of slopes and subtleties to the greens. They're rolling really well, so you have to stroke it on a good line.”
Maguire, who recorded her first top-10 finish on US soil on the LPGA earlier in the year, carded six birdies, including two to start and three in the last seven holes.
“I've been playing well the last few weeks,” she added. “Got off to a really nice start this season, and trying to build on that momentum. “
It's nice to come back to a course that I've been to before and I did well on last year.
Tavatanakit heads a star-studded leaderboard after a stunning bogey-free six-under 66.
The 21-year-old turned pro shortly after finishing 26th in the 2019 ANA Inspiration, winning three times on the Symetra Tour that year.A beneficiary of two ANA Inspiration amateur invites before turning professional, Tavantanakit said: “It helped playing the course at a really young age, seeing it differently.”
One of the greatest characters on the LPGA, Feng returned to the LPGA for the first time this week since November 2019.
“This is my first tournament in 13, 14 months, so I am mentally very fresh and I feel like my body is maybe back to like 25,” said the 31-year-old.
In only her second week back playing, Michelle Wie is also to the fore after a two-under 70.