Jason Day summed it up best — “Putting is the biggest equaliser,” he said after a 68 allowed him to outscore world No 1 Rory McIlroy by two and a struggling Jordan Spieth by seven in the opening round of the Deutsche Bank Championship, the second leg of the FedExCup Playoffs, at TPC Boston.

No matter that Zimbabwe’s Brendon de Jonge shot a six under 65 to lead by two from nine 68 shooters in Luke Donald, Colt Knost, Kevin Chappell, Ian Poulter, Matt Jones, Harris English, Charlie Hoffman, Henrik Stenson and Rickie Fowler.

This week is all about the new Big Three and it was the in-form, PGA champion Day who used his blade to steal a march on his rivals for the FedEx Cup and the world No 1 crown.

After a birdie-birdie-birdie start, the Aussie picked up two more shots on TPC Boston’s front nine to get to minus five, then dropped few shots coming home in treacherous, breezy conditions on ice-rink slippery greens.

“I'd like to say big, but it isn't,” Day said when asked how big the hole looks to him right now. “I'm putting some good rolls on it and then reading the putts is obviously key.

“Over the last seven weeks my speed has been fantastic, that's why I'm rolling putts in. I can go in and fully believe and trust that the line I'm picking is correct.”

“I didn’t drive today as good as I should have, but I hit a lot of greens,” said Day, who hit nine fairways and 14 greens in regulation. “Putting is the biggest equaliser. If you’re putting well you can turn a bad hitting day into a fantastic round. If I had to choose one, putting is helping me the most with the confidence.”

Spieth, unusually, had a nightmare on the greens to contrast with a dream day from the tee. 

He hit 12 fairways but missed seven greens and took 33 putts, opting not to speak to the press afterwards after missing all seven of his attempts to scramble for par.

It all added up to a four over 75 featuring four birdies and eight bogeys with three of those coming in his first five holes.

If it was a frustrating day for Spieth, it was equalling trying for McIlroy, who is hitting the ball superbly despite his lack of competitive practice.

Still, his rustiness on the greens was evident and he three putted twice, incuding his final hole, finishing bogey-bogey to take much of the gloss off a one under 70 wirth a share of 22nd.

“I felt like I hit a lot of good putts today that didn’t go in, and that probably had to do with the speed,” said McIlroy after 31 putts.

“I think my driving the ball, I think my short irons are pretty good,” McIlroy said. “I think my mid-to-long irons, especially my long irons, I had a couple of iffy ones out there today. I can sharpen that up a little bit. And obviously on the greens.”

Asked how you rebuild confidence (or knock off rust) after a lenghty layoff, McIlroy said: " I think the more that you see good shots and you have committed, solid shots to your targets, that builds confidence in itself.

"I took quite a lot of positives from the PGA a couple of weeks ago. And I've kept going here. I felt like I hit the ball very well. These greens are probably the fastest I've putted on in a while. The greens at Whistling weren't too quick, and before that I was putting on -- I don't know if you call them greens at Chambers Bay. So these are a bit of an adjustment. 

"I was hitting the ball a little bit too hard at times and under reading them, which you can do on fast greens. The more pace the green has the more it's going to swing. I just need to adjust to that.”

He’s not chasing Day just yet.

"Not really, not when it's the first round. I obviously saw that he got off to a great start. But it really doesn’t change how I play or how I think out there. 

“At that point I think it was 1-over par, so I was just trying to get it back into red numbers for the day and finish there. 

"It would have been nice to play the last few holes a little better. But it’s still a solid score in these conditions, and I don't think I'll be too far behind at the end of the day."