Phil Mickelson has announced that he will miss this year's US Open to attend his daughter's High School graduation. 

The US Open is set to begin on June 15th, the same day that Mickelson's daughter Amanda is making her graduation from Pacific Ridge School in California.

Mickelson had considered delaying a final decision on whether he would take part in the tournament until closer to the opening round. But with the final qualifying stage of the tournament coming up on Monday, he informed the USGA of his decision to skip the event.

The US Open is the last major title that Mickelson needs to win in order to be the sixth man to win a career Grand Slam.

Speaking to the New York Times, Mickelson said he feels duty-bound to be at the graduation.

"As I look back on life, this is a moment I’ll always cherish and be glad I was present. There’s no greater joy as a parent."

Mickelson's last tournament victory was the 2013 British Open.