Like most major golf championships, the U.S. Open is steeped in history and tradition. Punishing rough, lightning-fast greens and severe summer heat are all synonymous with the season’s second major.

Since the summer of 2000, the tournament has been dogged by an important question: Is this the year Phil Mickelson wins?

The hall of famer has five career majors (three Masters, one PGA Championship and one Open Championship), but since his second-place finish at Pinehurst No. 2 in 1999 to the late Payne Stewart, Mickelson has been agonizingly close to winning his national championship on five occasions.

Some of those second-place finishes were good showings, like in 2002 when Tiger Woods won at Bethpage Black. Others, led by his collapse at Winged Foot in 2006, are among the most painful losses in golf history. Regardless of how dramatic or spectacular the second-place finishes have been, history will look upon them as failures until Mickelson captures a U.S. Open title.

Mickelson turns 46 on Thursday. He will be greeted at every tee box and green with support and birthday wishes from Pennsylvania golf fans, but a question lingers: Is this Lefty’s last legitimate shot at winning the one major title that has eluded him?

At first glance, it looks like the window may have already closed.

Only two players in history -- Jack Nicklaus at 46 and Julius Boros at 48 -- have won majors after turning 46. Mickelson has also battled chronic arthritis over the past several years, and his last victory on the PGA Tour came almost three years ago at the 2013 British Open. 

You could make the argument that the above description sounds like a player who will never win another a golf tournament, let alone another major championship.

But this is Phil Mickelson we’re talking about. If there’s one thing that has been consistent about him during his career it’s that there is absolutely nothing consistent about him. You never know what he will do next. Television commentator David Feherty once compared watching Mickelson play to “watching a drunk guy chase a balloon along a cliff.” Mickelson’s game is that volatile at times, but it’s that same energy and unpredictability that has produced some of golf’s greatest wins and attracted legions of fans.

Mickelson has been steady so far this season, racking up five top-10 finishes on the PGA Tour, including a second-place finish at Pebble Beach. He leads the PGA Tour in scoring average and blew away the field in the strokes gained putting statistic last week in Memphis while adding another second-place finish to his 2016 record.

Those numbers don’t describe a washed-up 46-year-old veteran who hasn’t won in three years.

Mickelson has also played full-time on the PGA Tour since 1993 without any significant injury. His arthritis is controlled by medication, and he is taking full advantage of the advances in fitness, nutrition and technology that are keeping players relevant longer. All of the sudden, 46 is the new 36 on the PGA Tour.

At the end of the day, numbers don’t tell you a thing about a player’s desire, passion and work ethic.

Mickelson’s off-season included breaking off his relationship with longtime swing guru Butch Harmon.

He dedicated himself to getting back to an elite level by making significant changes with new swing coach Andrew Getson. A player who puts that amount of time and energy into searching for improvement certainly doesn’t sound like a guy who feels his best golf is behind him.

The greatest hurdle for Mickelson may not be age, the challenge of Oakmont or the game’s young guns.

It might be that he wants this championship too much. He wants it so bad that he could prevent himself from reaching golf’s Mount Rushmore, joining Gene Sarazen, Ben Hogan, Jack Nicklaus, Gary Player and Tiger Woods as the only players in golf history with all four professional majors.

You never really know what can happen when Lefty tees it up, but one thing is certain: If Mickelson is in the hunt this week, we’re in for a U.S. Open of epic proportions.