How many more majors can Mickelson win?

Phil Mickelson celebrates winning the 2013 The Open Championship trophy at Muirfield Golf Club. (Photo: Paul Cunningham USA TODAY Sports)

GULLANE, Scotland - On Monday morning Phil Mickelson began the first full day of his reign as the "champion golfer of the year," the moniker bestowed on the winner of the British Open.

His victory at Muirfield was his fifth major crown, giving him titles in three of the four majors, one shy of the career Grand Slam.

The question to ask now of the 43-year-old Mickelson: How many more majors can you win?

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Mickelson is only a putt or two, maybe a bounce or two, from being the reigning U.S. and British Open champ. Last month at Merion in Ardmore, Pa., Mickelson had at least a share of the lead after the first three rounds of the U.S. Open, before faltering in the final round and finishing a heartbreaking second for a record sixth time.

Give Mickelson this: He's resilient.

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"He looks forward," Mickelson's longtime caddie Jim "Bones" Mackay said.

"You have to be resilient in this game because losing is such a big part of it. And after losing the U.S. Open, it could have easily gone south," Mickelson said. "But I looked at it and thought I was playing really good golf. I had been playing some of the best in my career."

Majors these days always seem wide open. Since Tiger Woods stopped winning them in bunches - his last title came at the 2008 U.S. Open - there have been 21 major championships. Only three players in that stretch have won more than one:

*Padraig Harrington, 2008 British Open and PGA Championship.

*Rory McIlroy, 2011 U.S. Open, 2012 PGA.

*Mickelson, 2010 Masters, 2013 British Open.

Harrington, 41, has rarely challenged since changing his swing following his run of three major titles in just more than a year. McIlroy is in a slump but the 24-year-old is too good not to break out of it soon. Next year if not this.

And Mickelson, who has won three times worldwide this year, climbed back to No. 2 in the rankings and clearly plans to continue to be a threat going forward.

There is plenty of talent out there who will challenge: Justin Rose, Adam Scott, Lee Westwood, Luke Donald, Henrik Stenson, Martin Kaymer, Hunter Mahan. Jordan Spieth, 19, was near the top of the leaderboard midway through the British Open.

But consistently challenging at major championships is no easy feat.

Westwood has eight top-threes since 2008 but has never closed the deal. Luke Donald rose to No. 1 in the rankings but hasn't been able to finish No. 1 on the leaderboard at a major. Kaymer, Bubba Watson, Keegan Bradley and Webb Simpson are major champions, but have not shown they can be consistent threats.

Rose, one month after his breakthrough, missed the cut at Muirfield.

Scott showed Mickelson-like resiliency by winning the Masters this year after his epic collapse last year at the British Open (bogeys in the final four holes to lose to Ernie Els). He has been in the mix a bunch recently, and despite another stretch of bogey-bogey-bogey-bogey after taking the lead in the British Open, he doesn't seem likely to go away.

Woods has been close during his five-year drought, but has faded away too often on the weekends. The intimidating presence of the past doesn't seem so intimidating anymore ... at least as long as his putter fails on major weekends.

Mickelson took a while to earn his first major title - he began his major career 0-for-42 - but then he got hot, winning a major in three consecutive years.

But after his epic collapse at the 2006 U.S. Open, it took a while to get back on the board - his next win came at the 2010 Masters.

It took three years to get back in the winner's circle, but only one month after the most recent heartbreak.

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There's that resiliency again.

That's one reason Mackay expects many more victories in the years ahead.

"How many people are going to build a practice facility in his yard post-40? He wants it ... He works real hard and he wants it," Mackay said, explaining why the tears came so easily. "He really, really wants it."