AUGUSTA, Ga. -- Three-time Masters Champion Phil Mickelson said the LPGA should reverse its decision to penalize Lexi Thompson and give her the trophy from last week's ANA Inspiration.

Thompson was given a 4-shot penalty on Sunday during her final round because the day before she slightly moved her ball after marking it. A viewer emailed a complaint, and the LPGA penalized her the next day. She ultimately did not win the tournament because of it.

While several golfers have come to her defense, Mickelson said he believes golfers are getting a little "lax."

"I know a number of guys on tour that are loose with how they mark the ball and have not been called on it," Mickelson said on Tuesday at Augusta National. "They'll move the ball two, three inches in front of their mark, and this is an intentional way to get it out of an impression. I think that kind of stuff needs to be handheld by the tour."

Mickelson said the Tour needs to deal with issues directly and tell golfers when they notice them moving their ball a little too much and start by giving golfers a warning.

While Mickelson repeatedly said he didn't want to comment on the specific issues involving Thompson, he ended up saying that a tournament should not be decided by a viewer complaining on a 1-foot putt like Thompson's.

"I think it should be reversed. I think she should be given the trophy," he said.

Mickelson said everyone has done it, intentionally or not, and that it was easy to see how it could happen to Thompson with her standing next to the ball instead of behind it where it is easy to draw a line.

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