Four holes. That's how long it took Dustin Johnson to choose a new putter for the BMW Championship. Unhappy with his T8 showing at the Deutsche Bank Championship — where he ranked T41 in strokes gained: putting — the U.S. Open champion traded in his TaylorMade Ghost Tour Dayton 62 putter for a TaylorMade Spider Limited mallet at Crooked Stick.

The change produced one of Johnson's best putting rounds of the season. Along with shooting an opening-round 67, he led the field in strokes gained: putting (plus 3.947) with the new mallet that didn't arrive at the course until Wednesday afternoon.

"I messed around with it before, but, no, just I felt like last week and past few weeks I've just been struggling to get the putter on line, like the line that I was seeing," Johnson said. "And so yeah, [TaylorMade Tour rep Shawn Mullin] sent me one of those and I started rolling it and it felt pretty good. So I putted with it like the last four holes yesterday, because I didn't get it until like late in the round."

Johnson was spotted testing two putters on Thursday morning before his round — the Spider Limited he used, and a Spider Limited Red that happens to be the same putter Jason Day's had in the bag since RBC Heritage.

After giving both a try, Johnson opted for the more subdued version that has a charcoal grey crown and is comprised of a lightweight 6061 aluminum body and 304 stainless steel frame that positions the weight along the perimeter for improved stability. The larger head also reduces head twisting, keeping the face square at impact.

"The practice with it this morning was really good, so I kept it going and it rolled really nicely today," Johnson said. "So, I know it works, so if I miss putts, it's not the putter, it's me."

The decision to go with a mallet represents a significant change for Johnson, who typically uses an Anser-style blade. Just like Rory McIlroy, who made a similar putter change at The Barclays, Johnson felt it was time for a new look to get the ball back on line.

Johnson has been finicky with the putter over the course of his career, sometimes bouncing between numerous models during of a tournament. But nearly every putter he's used has been a blade model.

It's impossible to predict if the success will continue, but for at least one round, Johnson had the new putter going at Crooked Stick.