DUBLIN, Ohio – Phil Mickelson will likely withdraw from the U.S. Open.

He instead will attend his daughter Amanda’s high school graduation.

Mickelson informed the U.S. Golf Association of his decision earlier this week to be at Pacific Ridge School in Carlsbad, Calif., instead of Erin Hills in Wisconsin for the first round of the U.S. Open on June 15. That’s when Amanda, the school president, will give the commencement speech for the school. Ceremonies start at 10 a.m. Pacific time.

Mickelson will wait until the last minute to withdraw in case foul weather would delay the first round of the U.S. Open or something would happen where the commencement ceremonies were to be moved.

“I don't know what will happen, but it doesn't look very good,” Mickelson said after his third round of the Memorial at Muirfield Village Golf Club. “It would have to be something unforeseen. … I'm always holding out hope. As you look back on life, there are certain things you need to be there for.”

Mickelson, who has finished second a record six times in the U.S. Open, needs only a win in the national championship to become the sixth player to complete the career grand slam. Mickelson, who turns 47 on June 16, said the decision was difficult but he didn’t waver on his commitment to his family.

“Obviously it's a tournament that I want to win the most, and the only way to win is if you play and have a chance,” said Mickelson, who has played in 26 U.S. Opens. “But this is one of those moments where you look back on life and you just don't want to miss it.

“I'll be really glad that I was there and present.”

Mickelson said his daughter, who will attend Brown University, knows how important the U.S. Open is to her father and said she would understand if he played instead of going to the graduation.

“She's very supportive,” he said. “She's always been. But it's one of those things that you just show up. You just need to be there. It wasn't really something that we discussed, because it really wasn't much of a decision.”

This isn’t the first time Amanda has played into Mickelson’s equation that is the U.S. Open. In 1999 at Pinehurst, Mickelson said he would leave on Monday even if he was in a playoff to be with his wife, Amy, as she gave birth to the couple’s first child. He had a beeper with him throughout the tournament in case Amy went into labor.

Mickelson lost in a thrilling duel with Payne Stewart on Sunday, with Stewart making a 20-foot putt for par on the 72nd hole to topple Mickelson by one shot. He famously grabbed Mickelson’s face and said, “Good luck with the baby. There’s nothing greater than being a father.”

Amanda was born the day after the U.S. Open ended.

“I go back and every year at the U.S. Open, I think back about that '99 Open. The birth of your child, any child, but especially your first child is the most emotional event you can ever experience and share together with your wife,” Mickelson said. “And I always think about that at the U.S. Open. I think about Payne Stewart and I can't believe how quickly time has gone by.

“Here she is turning 18 and moving off to college and I'm so proud of her. And she's a special person. I'm excited to see what she has to say at her commencement.”