PONTE VEDRA BEACH, Fla. — And the winner of the 51st Players Championship is …

Well, we’ll have to wait until Monday morning to find out.

Rory McIlroy and J.J. Spaun ended the 72 holes at TPC Sawgrass in a deadlock at 12-under and will duel it out beginning at 9 a.m. Monday in a three-hole aggregate playoff on holes 16, 17 and 18.

“Everyone expects him to win,” Spaun said of McIlroy, a 27-time PGA Tour winner. “I don’t think a lot of people expect me to win. I expect myself to win. That’s all I care about.”

It was a wild day at Sawgrass, where dangerous weather halted play for four hours at 1:15 p.m.

At the time, McIlroy held a one-shot lead, at 12-under, over Spaun, who took the 54-hole lead into the day.

When the weather delay ended, it took just seven minutes for McIlroy to turn his one-shot lead into a three-shot bulge when he birdied the 13th hole and Spaun bogeyed 11.

At that moment, McIlroy was 13-under par and trailed by Spaun, Danny Walker, Akshay Bhatia and Tom Hoge, all of whom were at 10-under par.

From there, McIlroy, who won the Players in 2019, failed to put it away, leaving the door more than ajar for Spaun.

McIlroy bogeyed No. 14 after a poor drive, but 14 is the toughest hole on the course.

With a Spaun birdie on No. 14 behind McIlroy, he shaved the deficit to one shot.

McIlroy’s biggest mistake of the day was his failure to birdie the par-5 16th hole, the easiest hole on the golf course.

Spaun birdied 16 and tied the lead at 12-under.

Both players parred 17 and 18 to send the tournament to its first Monday finish in 10 years, when Rickie Fowler won in a playoff in 2015.

McIlroy, who began the day four shots behind Spaun, shot a 4-under-par 68 to Spaun’s even-par 72.

“I’m standing here feeling I like I should have gone home with a trophy today,” McIlroy said afterward. “But hopefully I’ll come back and go home with a trophy tomorrow. I hit a pretty bad tee shot on 14, then had two good chances on 15 and 16. Two good chances slipped by there. Then, I hit a good shot on 17 that spun back on the collar to an awkward shot.”

The 34-year-old Spaun, a journeyman who’s won once on the PGA Tour, looked shaky to start the day with the lead.

He didn’t birdie a hole until the par-5 ninth.

“I knew it wasn’t going to be easy,” Spaun said. “I just put a lot of faith in myself and my caddie. Once I made birdie on nine, that kind of turned the tide for me.

“Then, the little [weather delay] break we had helped me regroup and reset, and I came back with a different mindset instead of being so nervous. Starting the round, I was a little tentative, a little scared. [The weather delay] I think put me in a pretty comfortable spot to finish off the round.”

Spaun said losing the lead coupled with the weather delay helped calm him.

“I had nothing to lose,” he said. “Now I’m trying to catch Rory, and I can’t really control what he does, but I can control what I do. And I just started committing to my shots and my swing and trusting it more. Because … now when I’m hunting, it’s easier to let it go.”

To his credit, Spaun made a gutsy par on the 18th hole with McIlroy already in at 12-under and Spaun needing par to force the playoff.

Spaun’s tee shot on 18 trundled into the pine straw to the right of the fairway, and he ripped his approach shot to 30 feet from the cup and two-putted for the par.

As it always is on this golf course, there was a fascinating game of cat and mouse, with the players aware of what each other was doing.

“I was watching [McIlroy] the entire time,” Spaun said. “This is a course where decision-making is a huge process, so I had to know what I needed to do and what [McIlroy] was doing.

“I ended up grinding it out and I’ve got another chance tomorrow.”