Adam Scott rose to the top of the leaderboard on Friday at the World Golf Championships-Cadillac Championship in Doral, Fla.
Scott, bidding for his second victory in a row, shot a 6-under-par 66 at the par-72, 7,543-yard Trump National Doral and opened a two-stroke lead over Rory McIlroy and defending champion Dustin Johnson.
After 36 holes, Scott was at 15-under 134. Johnson posted the low round of the day on the Blue Monster with an 8-under 64 and McIlroy carded a 65.
Scott is the hottest golfer on the PGA Tour, having won the Honda Classic last week and tying for second in the Northern Trust Open two weeks ago. He could become the first player to win back-to-back weeks on the tour since Billy Horschel in 2014 at the BMW Championship and Tour Championship.
"I think overall, it was just a lot of good stuff," Scott said. "Enough quality shots and enough quality putts to negate a couple of mistakes out there. But they can easily happen on this golf course.
"So I'm glad there was enough of the good stuff to keep me up on top and kind of setting the pace after halfway."
Danny Willett was alone in fourth at 7-under 137 after a 69 and Bubba Watson was tied for fifth with Charley Hoffman at 6-under.
Watson, who won the Northern Trust Open two weeks ago for his ninth career victory, fashioned a 69 and Hoffman a 70 in the second round.
Phil Mickelson held a two-shot lead earlier in the day but made some mistakes, including a three-putt bogey on No. 13 and a double-bogey on No. 15, that dropped him into a tie for seventh with Paul Casey at 5-under 139.
Mickelson finished the round with an even-par 72 after coming home with a 40 on his final nine. Casey had a 68.
Johnson was mistake-free during the second round, collecting eight birdies and no bogeys on the way to his 64.
"I think the golf course is fantastic. It's in great shape," Johnson said. "The greens are perfect. But it's not an easy golf course. ... You can't take it easy anywhere out here."
McIlroy wielded a hot putter in the second round, needing only 23 strokes on the greens after requiring 33 putts in round one. With a win this week, he could move from No. 3 to No. 2 in the World Golf Ranking.
"I just needed to play a round without as many mistakes," McIlroy said. "The birdies were there. I've been making birdies. That's not been the problem. It's eliminating these mistakes that I've been making, and to play a round with only one bogey was really nice.
"I'm probably happier about that than the eight birdies I made out there to be honest with you, because the last few rounds, it's just been great shots mixed with poor shots."
Jordan Spieth, ranked No. 1, made four birdies and four bogeys in a round of 72 that left him in a tie for 12th at 3 under.
First-round co-leaders Marcus Fraser and Scott Piercy struggled to 77s and fell back at 1 under at the midpoint of the tournament.
