The 48-year-old overhit a putt at the 13th hole at Shinnecock Hills, and upon realising it would roll of the green, ran after his ball and hit it back in the opposite direction.
He was given a two-shot penalty, although some of his fellow players and pundits felt as though he should have been disqualified. He went on to finish tied for 48th.
He was also penalised at the Greenbrier Classic last weekend for tapping down some long grass with his club.
“I made a big mistake and you know, I wish I could take it back, but I can’t,” Mickelson said after an even-par opening round of 70 at the Scottish Open.
“But the thing about this is throughout my career, 25 years, there have been a lot of times where I have had to be accountable for decisions I did not make. And the reason why this has actually been easier: it was my own fault.”
“The backlash is my own fault… I have had mental lapses… throughout my whole life. It’s not like it’s new. That was just one of the worst ones.”
Mickelson insisted he had not been avoiding the media this week, saying that he had been to Paris and Carnoustie to prepare for September’s Ryder Cup and next week’s British Open respectively.
“Not trying to dodge anybody these first few days. I have been a little bit busy.”