Xander Schauffele said he is playing in this week's Sentry Tournament of Champions despite an ailing back.
The injury forced him to withdraw from Wednesday's pro-am but he teed off Thursday and carded a 3-under 70 in the opening round in Kapalua, Hawaii.
The seven-time PGA Tour winner and World No. 6 told reporters he isn't sure what the injury is and he has not yet had an MRI.
Schauffele, 29, said he dealt with the ailment at last month's Hero World Challenge, where he finished fourth.
"So this is new to me," he told reporters Thursday. "That's why I don't know how to answer these questions. I've never had to do this. Hopefully, we don't have these conversations more often."
Schauffele, who won this event in 2019, said the injury makes him uncomfortable when taking a full swing.
"I needed to lean on my putter on days like this when you're kind of just chipping it around," he said.
Schauffele said he hopes his back will hold up through the weekend at the Kapalua Resort's Plantation Course. He entered Friday tied for 26th and six shots off the lead.
"It's just a bummer," he said. "It's one of my favorite places to play, so hopefully that kicks into gear here in the next couple of days."
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