PONTE VEDRA BEACH, Fla.— Rory McIlroy began The Players Championship with a 65 on his scorecard, two tee shots that went into the water, and one lengthy dispute about where to take a penalty drop on Thursday.

McIlroy ended the day with 10 birdies for his lowest start ever at the TPC Sawgrass, leaving him tied with Xander Schauffele and U.S. Open champion Wyndham Clark on Thursday.

However, it was the drop on No. 7 that caused so much conversation with Jordan Spieth and Viktor Hovland, and some confusion on where he should drop.

“I think Jordan was just trying to make sure that I was doing the right thing,” McIlroy said. “I was pretty sure that my ball had crossed where I was sort of dropping it. It’s so hard, right? Because there was no TV evidence. I was adamant. But I think, again, he was just trying to make sure that I was going to do the right thing.”

McIlroy was 8 under for the day playing the par-4 seventh — his 16th hole of the round — when he pulled his tee shot. The land slopes toward a large pond, meaning the only gallery is on the opposite side of the fairway. Television replays saw the ball bounce, but not where.

The question became whether it was above or below the red hazard line. Had it landed above, McIlroy would take a one-shot penalty and drop it near where it crossed the line into the water. But if it was below the line — closer to the water — he would have had to take his penalty and drop back by the tee box on the 452-yard hole.

McIlroy had already taken his drop when his playing partners had questions. Spieth was heard to say, “We don’t know for sure that it crossed the line.”

“I’m pretty comfortable I saw it above the red line,” McIlroy said.

Things Get Testy

At one point it appeared to get testy between Spieth, McIlroy, and caddie Harry Diamond.

“Everyone that I’m hearing had eyes on it is … saying they were 100 percent certain it landed below the line,” Spieth said.

“Who’s everybody, Jordan?” Diamond said.

“Who are you talking about?” McIlroy added.

Spieth said all that mattered was what McIlroy thought.

A rules official arrived but was of little use without having seen the shots, and with the camera angle unable to capture exactly where the ball landed.

“I think my ball bounced above the red line, but it’s not definitive,” McIlroy told the official. “I’m pretty comfortable it did. We’re trying to check with TV and they can’t say.”