DUBLIN, Ohio (AP) — Erik Compton considers the Memorial a special week no matter how he plays, knowing his second heart transplant came from a donor in Ohio.

The opening round was even sweeter with three birdies on the back nine late Thursday afternoon at Muirfield Village for a 5-under 67, leaving him one-shot out of the lead after a day that featured a timely rally by Rory McIlroy and a surprising departure by Phil Mickelson.

When the day ended, Scott Stallings was atop the leaderboard with a 66 and hardly anyone noticed.

Compton has been an amazing story as long as he has played golf. He had his first heart transplant at 12, played in the Walker Cup after a solid career at Georgia, nearly died from a heart attack on his way home from the golf course in 2007, had a second transplant in May 2008, and earned his PGA Tour card for the first time last year through the Nationwide Tour.

“It’s just a great story, obviously, and it’s a great place — for me, it’s a special place,” Compton said. “For me, there’s not a day that goes by that I don’t think about my donor. To be able to play here, regardless of whether I play good or bad, it’s just always a nice week.”

It could have been another bad week for McIlroy.

Coming off back-to-back missed cuts that cost him his No. 1 ranking and ramped up the scrutiny, McIlroy took a quadruple bogey on his third hole of the tournament when he went from the bunker to the water, back over the pond to the drop area on a forward tee, and then into another bunker.

He blasted onto the green and took two putts for a 7, and there were murmurs from the crowd to see him at 4-over par so early.

The next 15 holes were much better, and he rallied for a 71.

“It wasn’t the start I wanted to get off to, being 4 over through three holes, especially after the last few weeks,” McIlroy said. “I was just like, ‘Here we go again.’ But I hung in there well, and proud of myself for the way I just fought back. To finish the round under par, I thought was a really good effort.”

Tiger Woods, playing in the group behind him, chopped up the 18th hole for a double bogey and still managed a 2-under 70.

“I didn’t do anything great and I didn’t do anything poorly,” Wood said. “I was just very consistent. And I think with the golf course being the way it’s set up, you just have to be that way. … Over the next three days, hopefully I can play as well as I did today.”

Mickelson wasn’t anywhere near those scores, and when his round ended, he was nowhere near the golf course. Mickelson walked out of the scoring hut after signing for a 79 — his worst score ever at the Memorial — and said he was withdrawing because of mental fatigue.

He said playing three straight weeks, followed by a trip to Europe for his wife’s 40th birthday, took too much out of him and he needed extra rest with the U.S. Open only two weeks away. Mickelson was among four players who withdrew after a 79 or worse, though none of the others are four-time major champions who were inducted into the World Golf Hall of Fame.

“I feel like it’s the responsibility of a player to see through your commitment and finish the tournament and so forth,” Mickelson said. “And I’m kind of overruling that just a touch, because I’m trying to think big picture on what’s the best way for me to get ready for the Open.”

The bigger picture might have been the fans in the gallery using their cellphones for photos of Mickelson, Masters champion Bubba Watson and Rickie Fowler. Mickelson has a peculiar way of sending a message, though he danced around a question of whether distractions played a role. He said only he struggled to focus from a busy month.

Watson and Fowler painted a different picture.

“It took Phil out of his game,” Watson said.

Fowler, a little more diplomatic, said the players had to restart their pre-shot routines because of the phone cameras.

“You could see Phil was a little fatigued and was having trouble blocking it out a bit,” Fowler said.

Muirfield Village was enough to get anyone’s attention, even those who had hardly anyone watching them. The first round was played under bright sunshine most of the day, and the course was as fast as it has been in years. Only four players managed to break 70 from the morning wave. Later in the afternoon, as the breeze subsided and some cloud cover arrived, Stallings, Compton and Spencer Levin made a surge.

Stallings had nine one-putt greens and chipped in for eagle on the par-5 seventh. Levin holed a 25-foot eagle on the seventh hole and made birdie on the eighth until dropping a shot on his final hole to join Compton at 67.

Defending champion Steve Stricker bogeyed his last three holes for a 73. Luke Donald, back to No. 1 after winning at Wentworth, felt like he shot much higher. Thanks to his superb short game, particularly three putts to save par from bunkers, he managed a 71.

McIlroy hit three balls in the water on his front nine, though he saved par on one of them. His putter saved him. The 23-year-old from Northern Ireland twice made 8-foot par putts, avoid a three-putt on the 18th with a 6-foot par putt and sprinkled in enough birdies to stay in the game.

The turning point came at the par-5 fifth, when he hooked his tee shot for the gallery. He cursed through clenched teeth, and holding his driver behind him, whacked himself in the back with the grip a couple of times. From the left rough, he played an aggressive fairway metal, low and hot and dead straight, avoiding the water down the left side of the fairway. The ball came up about 15 yards short of the green, and he pitched in for eagle.

“I see enough good shots out there to give me encouragement,” McIlroy said, one eye toward his title defense in the U.S. Open in two weeks. “There’s still a few that I don’t like, but as long as the good ones are in there, then you see the positives.”