Phil Mickelson made his first start this weekend on the PGA Tour since the U.S. Open at A Military Tribute at The Greenbrier in West Virginia, and finished 1-under par.

While he was never really in contention at The Greenbrier, all eyes were on the lefty after his rule-breaking debacle at the U.S. Open nearly a month ago when he hit his ball while it was still moving on the green out of frustration.

Mickelson had a brush with the rules again on Sunday — though this time he called himself on it, assessing a two-stroke penalty on an obscure rule that even the announcers didn’t notice at first.

Mickelson had teed up his ball in the tee box on No. 7 on Sunday at The Old White TPC, and was getting ready to hit. He saw some errant grass sticking up ahead of his ball, and naturally went to go pat it down with his foot.

It’s a move every golfer has done at some point in his or her career. Why not quickly move the grass out of the way so the ball doesn’t hit it?

According to United States Golf Association Rule 13-2, though, that’s a violation of the rules.

From the USGA, Rule 13-2: Improving Lie, Area of Intended Stance or Swing, or Line of Play:

By that definition, Mickelson did violate the rule.

Check out the shot and the encounter:

Perhaps the most impressive thing on Sunday, though, is that Mickelson recognized the rule violation himself — even though nobody else did and likely wouldn’t have ever called him on it.

In reality, the penalty didn’t change much. The leaders started out Sunday’s final round 13-strokes ahead of where Mickelson finished anyways.

He did, though, handle the rule violation much better than he did at the U.S. Open at Shinnecock Hills.

That has to count for something.

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