'What would we possibly be talking about today?' he asked in jest Tuesday.
Mickelson has a Masters championship and is the leading money winner with more than $4 million this year. But heading into this week's Western Open at Cog Hill Golf Club, the discussion once again centers on a loss -- his collapse at the U.S. Open.
'Well, I'm not ever going to forget it, that's obvious,' said Mickelson, making his first start since the U.S. Open. 'But what I'm not going to do is let it affect negatively my performance in upcoming majors. I've got two more. I'm playing too well, and I've got a system of preparation that has been helping me play some of my best golf.'
He led by one before the 72nd hole at Winged Foot two weeks ago. But he finished in a tie for second with Colin Montgomerie and Jim Furyk, one shot behind Geoff Ogilvy, after a double-bogey.
In between, Mickelson seemed to step back in time. And that was not a good thing for him.
He chose a driver over the 4-wood on the 18th tee and knocked the ball so far to the left it landed near the hospitality tents and matted in the rough. Then, he went for the green, rather than a safe shot. The ball hit a branch and traveled only 25 yards.
His third shot got buried in the bunker, and Mickelson was on his way to that double-bogey.
It was a startling finish, a flashback to those gunslinger days when Mickelson would turn reckless at key moments. He was 0-for-42 in majors as a professional before trying on the green jacket at the 2004 Masters. A PGA championship last summer and another victory this year at Augusta followed.
But his wife, Amy, said the loss at the U.S. Open might have been the most difficult. And when her husband returned to the rental house afterward, the family mobbed him.
Her husband was in a 'total state of shock,' and all Amy could do was tell him, 'I love you.'
Mickelson said the conversation with his three children went like this: 'Did you win, Daddy?'
'I'm sorry. Do you want pizza?'
The next day, the family returned home to Rancho Santa Fe, Calif. On Tuesday, Mickelson and his oldest child, Amanda, spent the day at a club pool. On Wednesday, the family celebrated Amanda's seventh birthday at Disneyland.
And a few days later, Mickelson went to practice at Royal Liverpool.
'One of my favorite things about Phil is from the day I met him, even in college, he's had this incredible perspective,' Amy Mickelson said. 'He's a very secure person. He knows who he is, what he's about and what he stands for. He's had highs and lows over the years. And there will be more lows.'
And the loss at the U.S. Open may have been the lowest point because he has played so well the past few years.
'He's really locked into a great way to prepare, and he's found what's working for him,' Amy Mickelson said.
But everything went awry at the U.S. Open.
Phil Mickelson defended his strategy on the final hole, saying 'the last thing I would do is question that.' The problems started earlier.
'My execution just wasn't what I wanted that week, and yet I fought and hung in there,' he said. 'And unfortunately, I just needed to hang in there one more hole and wasn't able to do it.'
So he walked away with perhaps the most difficult loss of his career. Yet with that disappointment, there was defiance.
'He'll never forget it, but it's also not a day that will define him,' Amy Mickelson said. 'That's just not the kind of guy he is.'