MEXICO CITY – Rory McIlroy had more trouble with his stomach than his ribs. The golf was just fine.

Playing for the first time in seven weeks because of a rib injury, McIlroy coped with a bad stomach and the high altitude with a 3-under 68 that left him one shot out of a six-way tie for the lead as the Mexico Championship made a strong debut Thursday.

Phil Mickelson and Lee Westwood, two of the four players who were in the field for the first edition of this World Golf Championships event in 1999, each shot 67 and were joined at the top by PGA champion Jimmy Walker, Ross Fisher, Jon Rahm of Spain and Ryan Moore.

Westwood and Walker each made it to 6 under until two bogeys over their final few holes.

McIlroy, who can return to No. 1 with a victory this week, had not competed since Jan. 15 because of a hairline fracture of a rib. That was never a problem. Leaning on his driver as he waited to tee off midway through his round, he said he spent most of the night feeling ill and “the altitude doesn’t help.”

He made the golf look easy, rarely getting out of position while playing aggressively early in the round and surging late with an eagle on the par-5 sixth.

“I don’t feel anywhere near as bad as I did in China last year when I had the same thing. So hopefully it’s just a day thing.”

LPGA: Michelle Wie rolled in several clutch putts and had six birdies in a 10-hole stretch to take a one-stroke lead after the first round of the HSBC Women’s Champions at Singapore.

The 27-year-old Wie, who has struggled with injuries and form since winning the U.S. Open in 2014, shot a 6-under 66.

“It’s a marathon this week, it’s not a sprint,” said Wie. “But I have to say I’m very proud of where I’ve positioned myself today.”

Five others were tied for second after 67s – Olympic champion Inbee Park, Brooke Henderson, Mo Martin, Anna Nordqvist and Ariya Jutanugarn.

EUROPEAN: Gregory Havret, Haydn Porteous and Alexander Bjork shared the lead after the first round of the Tshwane Open in Pretoria, South Africa, all carding 6-under 65s.

Fifteen players shot 67 or better at the par-71 course, a low-scoring opening round in the South African capital.

The leaders had a one-shot advantage over five players tied for fourth.

Havret made a blistering start with six birdies in his first nine holes before a more subdued back nine, where the Frenchman bogeyed Nos. 11 and 13.

NOTES

SIMON HOBDAY, the fun-loving South African golfer who won the 1994 U.S. Senior Open at Pinehurst, died after a fight with cancer. He was 76.

Hobday won five times on the PGA Champions Tour. He won the 1976 German Open and 1979 Madrid Open on the European Tour, and the 1971 South African Open was the biggest of his Sunshine Tour titles.