Rory McIlroy began the day three strokes behind leader Seung-Yul Noh, but has wasted no time making up that gap Saturday.
McIlroy made four birdies and an eagle in his first 10 holes, vaulting himself into sole possession of first place at the Deutsche Bank Championship being held at TPC-Boston in Norton, Mass.
Two bogeys in a row have now knocked McIlroy back to 10-under par, one stroke behind Noh.
Also in the mix is American Ryan Moore, who made four birdies and an eagle on his first nine. But Moore has also made three bogeys on Saturday, and finds himself at ten under par, also one stroke behind Noh.
Chris Kirk and Bryce Molder are both at eight under, while a trio of Americans are currently at seven under par: Jason Dufner, Jeff Overton, and Tiger Woods.
Woods tees off at 1:10, and he'll be playing with Barclays champ Nick Watney and runner-up Brandt Snedeker.
You can follow the rest of the leaderboard here.
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