Three holes later, Mickelson shook hands with his playing partners and headed for the clubhouse at Muirfield Village.
Mickelson, coming off a victory two weeks ago at The Players Championship, withdrew from the Memorial with an injury to his left wrist that he suspects happened while practicing out of the deep rough at Oakmont this week.
'I think it happened at Oakmont,' he told rules official Jon Brendle as they rode to the clubhouse in a cart, with Mickelson's wife sitting on his lap, and Shiatsu massage therapist Jim Weathers riding on the back.
'I don't think it's anything serious,' Mickelson said. 'I just can't put any pressure ... or grip the club.'
The timing could not have been worse.
Other than a skiing accident in 1994 when Mickelson slammed into a tree and broke his leg, the three-time major champion has never been seriously injured. He began working with celebrated swing coach Butch Harmon a month ago, then followed two third-place finishes with a victory at The Players against the strongest field in golf.
The extent of the injury has not been determined.
'I'm not really worried -- yet,' Mickelson said. 'It's never happened before, so I'm not really sure what to think of it.'
He plans to see a doctor on Friday.
Mickelson said he aggravated his left wrist while chipping out of the rough at Oakmont, where the U.S. Open will be played in two weeks. He took four pain pills Thursday morning and felt fine, and he was particularly pleased with how he hit the ball on the range.
Everything changed on the second hole, when Mickelson hit a wedge from 137 yards, and pain shot up his arm.
'It got really aggravated,' he said.
He played on, rubbing his wrist after almost every shot. It stung again after a 5-iron on the par-3 fourth, and while he was 2 under through six holes, the pain increased.
'He was holding his wrist all day,' Ryan Palmer said, who played with Mickelson and J.B. Holmes. 'He was holding a lot of shots.'
Woods was not surprised to hear that it might have happened at Oakmont, especially considering how much time Mickelson pours into his practice rounds at major venues.
'U.S. Open rough is pretty thick,' Woods said. 'You can do it. You can overdo it, definitely. If you hit a lot of shots out of there ... the wrist is pretty fragile. All he needs to do is just get one little tweak and that's it.'
Weathers, a former Green Beret with massive biceps, has PGA Tour credentials as a trainer. His business card describes him as a motivational speaker, flexologist and a master of Shiatsu, a massage therapy similar to acupuncture, using fingers instead of needles. He showed up on the ninth tee and went to work.
'I heard him say that the wrist felt jammed,' Palmer said.
Mickelson used his teeth to take the glove off his right hand to putt, and he debated pulling out after nine holes. But he played on, even after pulling his tee shot on the 10th.
'It's a little better,' he said to Weathers. 'It's bearable.'
'What if we have to hit out of the rough?' caddie Jim 'Bones' Mackay said to him.
'We're about to find out,' he said.
He hit a 210-yard shot from the rough over the back of the green and saved par. But he was done on the 11th. After a hybrid club off the tee, he laid up on the par 5 into a divot. Mickelson had only 100 yards to the hole, but wound up in the bunker.
'The wedge shot on 11 out of the divot jarred it pretty good,' he said. 'And I just didn't feel like I could hit a shot on 12.'
Mickelson said he 'half-clubbed it around,' taking easy swings to keep the ball in play. But as much as he wants to join an impressive list of winners at the Memorial, he is more concerned with the U.S. Open, where he is a four-time runner-up.
'The U.S. Open is more what we're gearing up for,' he said. 'As much as I'd like to play here and as excited as I was to play here and get back into the swing of it, I couldn't swing.'
Mickelson had planned to play next week in Memphis, and said he would still like to get in another tournament before the U.S. Open if his wrist will allow him to play.
The only other time Mickelson has withdrawn from a tournament was the 2004 Las Vegas Invitational because of food poisoning.
'Bones said he's never been injured and he has a high tolerance for pain,' Palmer said. 'I was looking forward to it because I'd never played with him. It was fun. But he made the right move. You don't want to risk that with the U.S. Open coming up.'