Rory McIlroy and Jordan Spieth have earned their spots atop the Official World Golf Ranking largely with elite ball-striking. According to the PGA Tour’s “strokes gained tee-to-green” metric, Spieth is plus-1.63 per round, which ranks second behind Bubba Watson (plus-1.87). McIlroy is at plus-2.00, which would far and away lead the tour if McIlroy had played enough rounds to qualify.

In short, both Spieth and McIlroy pick up more than 1.6 shots per round against the field from tee to green, but they get those results in very different ways.

Off the tee

McIlroy’s distance off the tee provides the foundation for his advantage. He has been in the tour’s top 10 in driving distance each of the last four years, and that length allows him to “go for the green” 74 percent of the time on par-5s and reachable par-4s.

Watson (77 percent) is the only player with a higher rate of going for the green on the tour.

Compare that to Spieth, whose distance off the tee (292.5 yards) is tied for 76th (but an improvement from his tie for 89th last season), and who goes for the green 57 percent of the time.

It translates to a significant advantage for McIlroy on the par-5s, where he makes birdie or better 57 percent of the time (second, behind Watson). Spieth’s 45 percent birdie-or-better rate on those holes exceeds the tour average of 41 percent but puts him 45th overall.

Iron accuracy

Where Spieth makes up the difference is in his ability to hit the ball close to the pin from almost any location. From the fairway, he’s tied for 17th in approach-shot proximity to the hole, but from the rough, he’s third.

McIlroy, who was extremely accurate from the fairway during his banner 2014 season (sixth in proximity from the fairway), is tied for 100th in that category this year, and he’s tied for 98th in overall approach-shot proximity.

It’s been no better for McIlroy with a wedge in his hand: He ranks 148th in approach-shot accuracy on shots from 50 to 125 yards.

Scrambling

The final piece for Spieth is outstanding play around the greens. He ranks seventh in scrambling (making par or better after missing a green in regulation), which is fueled by his tour-leading accuracy on shots around the green.

Two years ago, he was tied for 44th in accuracy on those shots.

By contrast, chipping and pitching have never been the strength of McIlroy’s game (he ranks 89th in scrambling this year, up from 145th two years ago). But his ability to hit greens in regulation (ranked seventh this year) keeps this part of his game from becoming a significant liability.