Dustin Johnson already has two runner-up finishes at the RBC Canadian Open at Glen Abbey Golf Course, and now he has a chance to improve on that.

Johnson backed up his 5-under 67 on Thursday with a 3-under 69 on Friday to get within four of Martin Flores' 12-under lead. Johnson is in the top 20 after Round 2 but without any real superstars in front of him.

This is not out of the ordinary for D.J. He finished second last year to Jhonattan Vegas and in 2013 when he lost by three to Brandt Snedeker. He feasts at this track and has continued to do so this week despite a leaky short game.

Johnson ranks outside the top 70 in strokes gained putting and outside the top 100 in strokes gained around the green after 36 holes. If he cleans that up on the weekend, Johnson could be looking at win No. 4 on the season.

"I'm hitting the ball good,"Johnson said. "I hit a lot of good putts that didn't go in the hole. I still feel really good with the putter. I feel like I'm rolling it well. I had a bunch of lip outs today but the golf course played a little bit tougher with the wind. But yeah, I'm in a good position going into the weekend."

Putting and short game have actually, maybe surprisingly, been two points of relative strength for Johnson so far this year. He ranks in the top 60 in both over halfway through the season (which is probably why he's already won three times). 

But Johnson has actually not played all that well since injuring his back at the Masters in April. He's gotten progressively worse since returning at the Wells Fargo Championship where he finished T2. That has come to a head in his last three tournaments where he's had two missed cuts and a T54 at the Open Championship.

It's not that his game has disappeared, it's just that he has not been as consistent as he was when he won the Genesis Open, WGC-Mexico Championship and WGC-Dell Match Play consecutively. Johnson said on Thursday that he feels like he's getting a little bit of that consistency back.

"The golf swing feels a lot better," Johnson said. "I'm starting to hit a lot of good shots, a lot more consistent ball flight. It's definitely moving in the right direction.

Johnson's driver has been his greatest weapon all year and is again this week with Glen Abbey's soft, wet conditions. He's No. 21 in the field in strokes gained off the tee despite displaying little-to-no accuracy and even inquiring about whether he could have fans move a car from a parking lot in Round 1.

The upshot for Johnson is that if his TaylorMade rock starts dropping on Saturday and Sunday, he could be off to the races. With nobody in front of him that has preeminent staying power, we could be in for a fun weekend of Johnson trying to run down guys with lesser talent.

And with his defense of the WGC-Bridgestone Invitational upcoming followed by the PGA Championship, it's a dangerous time for the No. 1 player on the planet to find his game once again.