He was bullish over the "putt-gate" controversy that threatened to overshadow the US Open, but now Phil Mickelson has had time to reflect and says he is "embarrassed" and "sorry."
The five-time major champion caused uproar in the world of golf when he ran after a moving putt on the 13th green and hit the ball back towards the hole at Shinnecock Hills.
In doing so, Mickelson incurred a two-shot penalty, which he claimed was better than what he could have run up had he let the ball run off the green. After his round Saturday -- his 48th birthday -- Mickelson said it was a deliberate act "to take advantage of the rules" and told his critics to "toughen up."
But he said in a text message to a select group of reporters Wednesday: "I know this should've come sooner, but it's taken me a few days to calm down.
"My anger and frustration got the best of me last weekend. I'm embarrassed and disappointed by my actions. It was clearly not my finest moment and I'm sorry."
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Spirit of the game
Mickelson was struggling to handle the difficult set-up and fast-running Shinnecock Hills course Saturday as he strived for a first US Open after a record six runner-up spots to complete the set of all four of golf's majors.
Seeing his ball sliding past the hole on the 13th, the left-hander set off in pursuit and sparked a storm of debate over whether he had acted contrary to the spirit of the game.
The USGA invoked Rule 14-5 which states a player "must not make a stroke at his ball while it is moving." The penalty is two shots, but some were calling for Mickelson to be disqualified.
Afterwards, Mickelson, who carded 81, told FOX: "I was just going back and forth and I'd gladly take the two shots over continuing that display.
"No question it was going to go down into the same spot behind the bunker. You take the two shots and you move on."
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'Good man, bad moment'
Asked whether he thought his actions were disrespectful, Mickelson added: "It was meant to take advantage of the rules as best as you can. I don't mean it in any disrespect and if that's the way people take it, I apologize."
According to USGA chief executive Mike Davis, Mickelson rang him later Saturday to discuss whether he should be disqualified but Davis told him he had been dealt with by the rules.
Mickelson refused to speak with reporters waiting after his round Sunday, but his wife Amy said: "He's a good man who had a bad moment.
"He's not perfect -- I'm not, you're not. It was very uncharacteristic."
Mickelson's playing partner Saturday was Andrew Johnston, who told BBC Radio 5 Live of the incident: "His body acted quicker than his brain.
"It's brutal out there and he was upset the way he played the previous holes. It just got to him."
Mickelson closed with a round of 69 in more favorable scoring conditions Sunday to finish 15 shots behind Koepka.
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Only five players in history have won the career grand slam -- Gene Sarazen, Ben Hogan, Gary Player, Jack Nicklaus and Tiger Woods.