The world number two, whose opening 75 was his first over-par score in the £6.4million season-ending event, was left to rue a number of missed opportunities before a bogey on the last after hitting his approach into the creek which runs the length of the hole.

"I think I turned a 62 into a 68 somehow," McIlroy said. "I hit a lot of good shots and didn't really hole many putts and it was the story of the day with what happened on 18.

"(I hit) a great drive, second shot had 207 (yards) to the pin into the wind. Maybe just was a little too aggressive with it and pulled it slightly and just got punished for a bad shot.

"It's okay," McIlroy said. "I've got a great afternoon of sport coming up, so I'm going to go home and sit myself on the couch and watch a couple of football matches and a rugby match and all will be well.

"I want to go out and play well tomorrow, try and post a good score and feel good about myself going into the next couple of months before I tee it up again."

At five under par, McIlroy was six shots behind clubhouse leader and Ryder Cup team-mate Rafa Cabrera Bello, who had surged through the field with a superb 63, the lowest score of the week.

Cabrera Bello, who won two and a half points from his three matches at Hazeltine, went to the turn in 33 before firing six birdies in his last eight holes to join team-mate Matt Fitzpatrick in the lead.

Fitzpatrick was six under par for his first eight holes after four birdies and an eagle, but bogeyed the ninth to reach the turn in 31.

Cabrera Bello said: "I knew I needed something special to catch up to the leaders, but I wasn't expecting something this low.

"It's been a very, very good year and I've pretty much accomplished every single goal and many of my childhood dreams as well."