Lexi Thompson battles difficult conditions and leader Ally McDonald in ANA Inspiration

Players have talked all week about the thickness of the rough at Mission Hills Country Club in Rancho Mirage, where heavy winter rains have helped turn deep grass framing the narrowed fairways into places where golf balls go to die.

Apparently, they weren’t joking.

Only five players managed to shoot in the 60s Thursday on the Dinah Shore Tournament Course in the opening round of the ANA Inspiration, the first major championship of the season that is offering plenty of major challenges to 112 of the best female golfers in the world.

Ally McDonald, yet to win in her third year on the LPGA Tour, birdied the 18th hole to get to four-under-par 68 and take the solo lead. Lexi Thompson, winner of this event in 2014, is one shot behind at 69 and is joined by tour rookie Linnea Strom of Sweden and Jin Young Ko and Hyo Joo Kim of South Korea in second.

No other player managed to score in the 60s on a course that played to an average of 73.8 strokes, more than a stroke-and-a-half higher than it did a year ago.

Former No. 1 and Hall of Famer Inbee Park, who lost in a playoff last year and opened with a one-over 73 Thursday, provided the day’s understatement: “It wasn’t easy out there.”

Three of the par fours — Nos. 3, 4 and 15 — have been lengthened from 15 to 35 yards each, and the greens are fast and firm. All of that puts a premium on keeping the ball in the fairways.

“It played really tough,” said 41-year-old Cristie Kerr, who is aiming for her third major title and is very much in the thick of things after shooting 70.

“I missed two 5-irons today, and other than that I played perfectly,” she said.

“I mean, jeez, we have so many long par fours now.”

Immediately after her round, Kerr headed to the range to work on her irons.

A year ago, 19 players shot in the 60s in the opening round, led by eventual winner Pernilla Lindberg’s 65; 55 players were under par. Thursday, only 28 players broke par.

Thompson revels in the major championship atmosphere of this event, and she has experienced the apex and nadir of her career in the California desert. She seemed on her way to a second major win in 2017 before being assessed a four-shot penalty the day after a TV viewer spotted her playing the ball from an incorrect position and called officials. She wound up second.

Thursday, she finished with two birdies and managed her way around the course by playing the aggressive style for which she is known.

“The rough is thick,” she said. “They brought in the fairways I think five yards on each side or something like that. The fairway is a lot tighter than I’m used to seeing, and the rough is up, so that’s a major championship. …

“The course is in probably the best shape I’ve ever seen it, honestly.”

Thompson hit drivers on the longer holes rather than playing conservatively to stay out of the rough, and with reason.

“If you miss the fairway, you want to get the shorter shot into the hole and not have too long of an iron from this rough,” she said.

Thompson hit only seven of 14 fairways and 11 of 18 greens, but needed only 26 putts and twice got up and down from the sand.

“I’m very happy with the way I just stayed strong the whole day and came out with three under,” she said.

Defending champion Lindberg got off to a rocky start with bogeys on two of her first four holes and shot a 73. She finished early in the day, before the wind increased in the afternoon, and despite a round that was eight shots worse than her first round a year ago, she’s hardly out of the running. Almost no one is. After all, there are 54 players, including Lindstrom, within five shots of the leader.

Former No. 1 Lydia Ko, who won the event three years ago, is one of 10 players only two off the pace.

“The mental side is going to be huge this week,” she said. “When you do get the birdie opportunities, try and grab them. It’s not a course that you’re going to see 10-under par for a round.”

Among those near the top of the leaderboard, Jessica Korda had the most unusual scorecard with seven birdies, five pars, three bogeys and a double bogey on the way to a 70.

“It was a serious roller coaster,” she said. “Glad I got off it on 18.”