Remembering the Time Phil Mickelson Lost His Mind at the U.S. Open, and Acted Like a Child at Shinnecock

The 126th U.S. Open begins Thursday at Shinnecock Hills Golf Club in Southampton, N.Y., with the best players in the world teeing it up on one of the hardest golf courses on the planet.

One legendary golfer who will not be in the field is Phil Mickelson. The 55-year-old, who is one U.S. Open win short of a career grand slam, had his five-year exemption from winning the 2021 PGA Championship expire and he didn't try to qualify for this year's event as he has been away from LIV Golf while dealing with a family health issue. Mickelson was also in the news last week when a report surfaced about him being kicked out of his private club in San Diego over allegations of inappropriate contact with a female employee.

MORE: The 10 Best Golfers Who Haven't Won a U.S. Open Yet, Including Scottie Scheffler

While Mickelson won't be a Shinnecock this year, he was in the field in 2018 at the famed course and he had an embarrassing moment during the third round that left everyone stunned, and not in a good way.

What Mickelson did in the 2018 U.S. Open that drew the ire of everyone watching

Mickelson was on the par-4 13th hole in Saturday's third round when his bogey putt slipped past the cup and started rolling down the hill. Instead of waiting for it to come to a complete stop, Mickelson jogged over to the ball and whacked it back toward the hole while it was still moving.

Fans standing around the green could be heard gasping in disbelief over what they had just seen Mickelson do because that's not even something you'd see during a hacker's Saturday morning round at a public course, let alone by one of the best players ever at the U.S. Open. That fact that he was seen having a laugh about it as he walked off the green only made it an even worse look for a guy who should know a lot better than to do such a thing.

Mickelson then missed his next putt before tapping in for quadruple bogey eight. He was later issued a two-stroke penalty for hitting a moving ball.

"During play of the 13th hole Phil Mickelson made a stroke on the putting green at the time his ball was moving," the USGA said at the time in a statement. "As a result, he incurred a two stroke penalty for a breach of Rule 14-5. His score for the hole was 10."

Here's how that played out

What Mickelson said after the round made it even worse

Mickelson didn't hide from the media after the round. Instead he addressed his mind-boggling move head-on, stating that he did it on purpose because he didn't want to end up having to hit a harder shot if he let his ball keep rolling.

"I know it's a two-shot penalty, and at the time I just didn't feel like going back and forth and hitting the same shot over," Mickelson said at the time. "I took the two-shot penalty and moved on. It's my understanding of the rules. I've had multiple times where I've wanted to do that. I just finally did.

"It was going to go down in the same spot behind the bunker. I wasn't going to have a shot. I don't know if I was able to save a shot or not. I know it's a two-shot penalty hitting a moving ball. I tried to hit it as close as I could on the next one, and you take the two shots and move on."

That's just some unbelievable stuff to hear from someone who at the time had five major championship victories under his belt.

But he didn't stop there. Mickelson had the gall to say he didn't think his move was disrespectful to the U.S. Open or everyone else playing in it.

"It's certainly not meant that way. It's meant to take advantage of the rules as best as you can. In that situation, I was just going back and forth. I would gladly take the two shots over continuing that display.

"I don't mean it in any disrespect. And if that's the way people took it, I apologize to them, but that's not the way it was taken. I took the two-shot penalty, moved on, and there's not much more to say."

Mickelson's post-round interview with Fox Sports' Curtis Strange is a hard watch all these years later:

How Mickelson finished in the 2018 U.S. Open

Mickelson rebounded from a brutal first-round 77 by shooting a one-under 69 on Friday to make the cut. Then on Saturday, thanks to that 10 on the 13th, he shot an 11-over 81. Mickelson closed out his week with another one-under 69 on Sunday to finish 16-over for the tournament, which gave him a T48 finish.

More U.S. Open from Sports Illustrated

• U.S. Open Picks, Props, Predictions: Betting Xander Schauffele, Matt Fitzpatrick and Patrick Reed
• One of the Greatest Shots in U.S. Open History Happened at Shinnecock. And It Came at the Perfect Time
• The Windmill, the U.S. Open, and Two Trailblazing Women Who Shaped Shinnecock
• 2026 U.S. Open Predictions: Our Picks to Win and Surprise at Shinnecock
• How to Watch the 2026 U.S. Open at Shinnecock on TV and Streaming; Past Champions and Future Locations

This article was originally published on www.si.com as Remembering the Time Phil Mickelson Lost His Mind at the U.S. Open, and Acted Like a Child at Shinnecock.

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This story was originally published June 17, 2026 at 6:00 AM.