But it also could have resulted in a disqualification, something that the rules committee of the U.S. Golf Association chose not to consider.
Rather than waiting for it to stop, he broke into a trot and when the ball was about 15 feet below the cup, and still in motion, he hit it back up the slope to above the hole.
It was not immediately clear what was Mickelson's motive in striking the ball.
"That's... that's stunning", commentator Joe Buck said. In fairness to Mickelson, the best aren't immune to a brain freeze or a meltdown and he'll surely put his act down to something like that. "But I'm in a decent position", he said after dropping back to five over overall.
Much debate has been made about the difference between Rule 14-5 - which was quoted as the reason for the penalty - and Rule 1-2. So it's not necessary to move on to (Rule) 1-2. It was amusing because I didn't think he hit that bad of a chip shot from behind the green in the first place.
"I know it's a two-shot penalty, and at that time I just didn't feel like going back and forth and hitting the same shot over", Mickelson said after his round.
"Phil really did want to understand how the rule operates", Davis said, via Randall Mell of the Gold Channel.
Mike Davis, chief executive of the USGA said later: "We want the US Open to be tough, but we saw some examples late in the day where well executed shots were not only not being rewarded, but in some cases penalized". It's amusing. I just wanted to get to the next hole and did not see that happening without the two shots'. Mickelson took a two stroke penalty before eventually making the shot. Yep, that's the difference in the rules.More news: Korean crypto exchange Bithumb says it lost over $30M following a hack
Mickelson's comments seem to suggest he was attempting to gain an advantage. Daly was on No. 8 in the final round when he took an 11 on the hole and signed for an 81.
An action taken for the sole objective of caring for the course is not a breach of rule 1-2.
"Phil knows the rules", Spieth told the media in Cromwell, Conn.
Hitting a moving ball incurs a two-stroke penalty, and Mickelson was eventually assessed with a six-over 10 at the par-four hole. "Yes, you read that correctly".
Reigning Open Champion and this week's defending Travelers Championship champion, Jordan Spieth was asked his views on the incident. In fact, it didn't even get them to that point, most golfers that often play during their lifetime will never shoot par on any course.
Stuart Appleby disagreed with the decision to use Rule 14-5 because, he said, it would require a player to be addressing the ball from a normal shot stance.
Some of the professional golfers said Lefty should have been disqualified, kicked out, tarred, feathered and strapped to the whipping post.
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