In 2017, Dustin Johnson used a TaylorMade Spider Tour Black that had no sightline on the crown. At the 2018 Sentry Tournament of Champions — where he happened to win by 8 strokes — DJ had two, perpendicular sightlines on his Spider putter; TaylorMade calls it a T-line. And if the reason why he changed putters doesn’t explain why you need to get fit, I’m just not sure what does.

Here’s what happened in an account from TaylorMade:

“[Dustin Johnson] was struggling with his putting end of last season, punctuated by his lost lead in China after struggling on the greens. Keith Sbarbaro [his fitter and VP of Tour Relations] met with him in Carlsbad at the putter lab to solve his woes. The Tour team built 12 identical Spider Tours, each with different sight lines (long, short, dots, etc.). He hit 5 putts (flat, 15 footers) with each sightline in the lab. The putters with the long lines he was aiming upwards of 10 inches left of the hole. The short line model(s) he lined up left edge. The one he used all last year with no line was 1 inch left of center, but the “T-line” model was right at dead center nearly every putt…”

It’s amazing to me that the World No. 1 golfer, who won four times in 2017, could be aiming upwards of 10 inches left of the target. I don’t care if it’s an old-school 8802-style putter with no sightline, that’s eye-opening to hear a golfer of his caliber can be that far off with his aim from 15 feet. It just goes to show how much the look of a putter, and the alignment lines, can have an affect on your aim. And it also explains to us mortals that we should be doing the same test for ourselves before buying a putter.

Apparently, DJ needs a “T-line” to aim properly. But every golfer is different. Next time you have access to a putter fitting, or any alignment feedback device, take advantage of it. Try different putters, models, styles and sightlines to see what works best for you… it just may save your putting.

Related: Dustin Johnson’s Winning WITB from the 2018 Sentry TOC