Dustin Johnson has finished each of the past three seasons ranked among the top three players in the world. He has more wins on the PGA Tour than any active golfer not named Tiger Woods or Phil Mickelson, and over the last year he’s won tournaments in Canada, Mexico and Saudi Arabia. By all accounts, Johnson is a singular talent. But despite a legacy that is seemingly unassailable, the 34-year-old has just one major victory.

Johnson knows this. Before last month’s PGA Championship, he acknowledged his frustration, telling reporters, “I’ve had quite a few chances, and I’ve felt like a few of them, I really didn’t do anything.” Days later, in the final round at Bethpage Black, he completed one of the best performances of his major career, according to Data Golf’s true strokes gained metric. He also bogeyed two of the final three holes, blowing a chance to catch Brooks Koepka. Considerably more bandwidth was spent on him having finished second for a second consecutive major, putting the final touch of his career grand slam of runner-ups and dropping to — you guessed it! — second in the world golf rankings than was spent on him being the only player in the field to shoot below par in all four rounds.

Some see in him the best athlete in the sport, a prodigious driver with a swing sequence deserving of a MoMA exhibit. At his best, Johnson makes the sport seem effortless; when everything gels, he is unsurpassable. In a game dominated by power, Johnson hasn’t finished a season ranked lower than sixth in average driving distance since he joined the tour in 2008. But others see a composite of underachievements, a man too talented, too physically gifted that a lone major win doesn’t suffice. It’s golf’s greatest talent plummeting down a flight of stairs on the eve of the biggest event of the calendar.

Johnson’s letdowns have become legend. There was the ground-club bunker gaffe at Whistling Straits that cost him a PGA Championship in 2010, the three-putt at Chambers Bay that cost him a U.S. Open in 2015 and the third-round 77 at Shinnecock during last year’s U.S. Open. The last time the U.S. Open was at Pebble Beach, in 2010, Johnson held a three-stroke lead after 54 holes before imploding with an 82 in the final round.

This points to Johnson’s true issue: It’s not that he struggles to perform at majors, but that he struggles to close them out. For some, this is legacy crippling, analogous to Michael Jordan or Tom Brady suddenly vanishing in the waning moments of the NBA Finals or the Super Bowl. But the notion holds water statistically. According to a round-by-round analysis of Johnson’s true strokes gained, his numbers plummet from 2.03 and 2.58 during the opening rounds of majors to 1.82 and 1.03, respectively, on the weekend. At nonmajors, however, his average true strokes gained spike after cut day and are at their highest on championship Sundays.

Sunday is DJ’s worst day Average true strokes gained for Dustin Johnson in majors and nonmajors by tournament round Avg. True strokes gained Tournament Round 1 Round 2 Round 3 Round 4 Majors 2.03 2.58 1.82 1.03 Nonmajors 1.58 1.40 1.61 1.70 Source: Data Golf

This is abnormal. Of the 10 worst major rounds in Johnson’s career, four came during Round 4. Relative to the field during the fourth round, Johnson averages 0.67 more true strokes gained at nonmajors than he does at majors.

For context, we compared Johnson’s career performance to a selection of his contemporaries and rivals. That negative disparity in the final round is larger than any of the contemporaries we sampled and contrasts mightily with that of Koepka, who averages 1.08 more true strokes gained on the final day of majors than he does at run-of-the-mill events.

Johnson doesn’t raise his game to a major level Average true strokes gained in the fourth round throughout the careers of notable golfers in majors and nonmajors Avg. True Strokes gained in Fourth Round Player Nonmajors Majors Difference Dustin Johnson 1.70 1.03 -0.67 Tiger Woods 2.93 2.50 -0.43 Justin Thomas 1.47 1.24 -0.23 Adam Scott 1.54 1.51 -0.03 Bubba Watson 0.80 0.79 -0.01 Phil Mickelson 1.57 1.72 +0.15 Jason Day 1.49 1.73 +0.24 Rory McIlroy 1.98 2.29 +0.31 Jordan Spieth 1.44 1.82 +0.38 Rickie Fowler 1.07 1.47 +0.40 Justin Rose 1.24 1.86 +0.62 Brooks Koepka 1.25 2.33 +1.08 Source: Data Golf

The only golfer among DJ’s peers to come close to his fourth-round letdown is Tiger Woods. But Woods has averaged a mind-melting 2.93 true strokes gained in Round 4s at nonmajors, by far the biggest figure in our sample, so a drop to a still-impressive 2.50 in majors isn’t exactly shocking.

Over the course of a four-day tournament, Johnson is still crushing the field — even at majors. His performance in true strokes gained at majors is 0.35 better than at nonmajors. When compared with the overall major splits of some of the top golfers, that difference is mostly average. In other words, Johnson’s championship problem is largely because of the fourth round.

Johnson still plays better overall in majors Average overall true strokes gained throughout the careers of notable golfers in majors and nonmajors Avg. true strokes gained Player Nonmajors Majors difference Brooks Koepka 1.00 2.01 +1.01 Jason Day 1.24 2.12 +0.88 Jordan Spieth 1.60 2.36 +0.76 Justin Rose 1.04 1.68 +0.64 Phil Mickelson 1.51 1.99 +0.48 Justin Thomas 1.29 1.67 +0.38 Rickie Fowler 1.32 1.70 +0.38 Dustin Johnson 1.56 1.91 +0.35 Rory McIlroy 1.68 1.93 +0.25 Adam Scott 1.37 1.58 +0.21 Tiger Woods 2.65 2.73 +0.08 Bubba Watson 0.83 0.86 +0.03 Source: Data Golf

The good news for Johnson is that his overall major performance is improving — even if it isn’t producing trophies. Much of Johnson’s reputation for failing to vanquish majors was cultivated prior to his 30th birthday. Indeed, the five best seasons of Johnson’s career by true strokes gained have come since he turned 30, in 2014. And that peak performance has manifested during majors, too, where he’s finished an average of nearly 10 spots better compared with how he finished in his 20s. Entering the Masters, only Jordan Spieth and Johnson had led at least 10 major rounds since 2014. This weekend’s U.S. Open at Pebble Beach — where DJ and Koepka are co-favorites — will be Johnson’s 19th since turning 30.

Johnson is getting better with age Average true strokes gained per round in majors for Dustin Johnson before and after his 30th birthday Career Before turning 30 After turning 30 Number of majors 22.0 18.0 Average finish place 31.1 22.0 Avg. true strokes gained Before turning 30 After turning 30 Overall 1.4 2.5 Round 1 1.2 3.1 Round 2 2.0 3.3 Round 3 2.2 1.4 Round 4 0.3 2.0 Source: Data Golf

It’s unlikely that Johnson could ever live up to the public’s expectations of him. The curse of appearing as though you were designed by a supercomputer is that the results must follow. Johnson is capable of producing any shot on a golf course, but his performance at majors, at least in terms of how the public writ large perceives it, understates how exceptional he is. And since the major-winning spout typically goes dry by a player’s mid-30s, the hourglass is running out for Johnson to show the world that he can win when it matters the most.