Dustin Johnson opens with 8-under round at the Memorial

Dustin Johnson set the pace early with 10 birdies on his way to an 8-under 64 at the Memorial.

Jason Day avoided his aggressive nature to try to catch him Thursday.

One day after Jordan Spieth referred to Johnson as the most talented player on the PGA Tour, Johnson opened with three straight birdies, made three straight birdies to close out the back nine, added four in a row on the back and wound up with his best score in his nine years at Muirfield Village. He had a one-shot lead over Brendan Steele, who holed out for eagle on the 18th for a 65.

Day, the No. 1 player in the world and a member at Muirfield Village, played in the afternoon as the clouds began to gather. The Australian rallied on the back nine with three birdies and an eagle, and he wound up two shots behind. His 66 was his best score in competition on the course Jack Nicklaus built.

Spieth’s putter saved him in a scrappy round of 70. Rory McIlroy, playing with Spieth, changed back to a conventional putting grip. That helped only so much in his round of 71.

So much attention was on the top three players in the world because of their ranking, having won five of the last seven majors, and because all three arrived at the Memorial coming off victories.

Johnson, with his power and on Thursday his putting, showed why Nicklaus and others think this “Big Three” will only get larger.

Matt Kuchar holed a 15-foot par putt on the 18th hole to join the group at 66 that included Hudson Swafford, who did all his damage on the front nine when he tied the course record with a 29.