Irishman Seamus Power claimed a one-stroke lead after the opening round of the St Jude Classic, where former world number Dustin Johnson was nearly flawless. He may add to that haul after an opening round in Memphis that included six birdies against a lone bogey, with a 6-footer for birdie on No. 18 giving him an advantage over the field. Mickelson and Koepka headline the group at 4 under, with the latter preparing to defend his U.S. Open title next week in NY.
Second-ranked Dustin Johnson was at 67 with Retief Goosen, Scott Stallings and seven others.
There are 11 players tied for second position, including reigning U.S. Open champion Brooks Koepka and Phil Mickelson at TPC Southwind. "I think it's the most underrated on tour".
Johnson had five birdies to go with his double-bogey on Thursday.
Power birdied two of the last three holes to cap a five-under 65 to claim the early clubhouse lead at TPC Southwind in Memphis, and his score held up for the remainder of the day despite 11 players all getting to four under par. Just need to continue to do what I do and obviously a three-peat would be fantastic.
His approach shot there landed on the edge of the water hazard and Johnson stripped off his right shoe and sock to take his stance with one foot in the muddy water - then saw his wedge shot find the hole.
"I actually didn't hit it very well and got lucky and it went in the hole", he said modestly.
"I didn't play well at all", he said. "We were kind of all over the place, but hope to figure this out for the rest of this week".
Phil Mickelson, Jordan Spieth and Rory McIlroy tee off together in the morning of the first round.
Corey Conner of Listowel, Ont., is 2 under while Nick Taylor of Abbotsford, B.C., and Ben Silverman of Thornhill, Ont., opened with 70s.