Jordan Spieth birdied the final hole to take a one-shot lead into the final round of the PGA Tour's season-ending Tour Championship.
The 22-year-old, one of five players who will automatically claim the FedExCup title this week, carded a birdie-two at the par-three last to close a two-under 68 and move one-shot clear of overnight leader Henrik Stenson in Atlanta.
After bouncing back from a dropped shot at the first with an eight-foot gain at the third, Stenson temporarily saw his lead cut to one when he followed a blemish at the tenth with a three-putt bogey at the 11th.
Paul Casey had closed the gap with back-to-back birdies at the sixth and seventh but failed to pick up another stroke all afternoon, while Rory McIlroy's four gains in a seven hole stretch around the turn briefly moved him within one of the Swede.
Stenson restored his two-shot cushion by rolling in a 22-footer at the 14th, only to see Spieth half the gap by sliding in an eight-foot gain at the next.
A double-bogey at the last from McIlroy saw him back four adrift, as a missed long-range par-save from Stenson at the penultimate hole saw Spieth move in to a tie for the lead heading to the last.
As the Swede two-putted from 30 feet for par to close a two-over 72, Spieth rolled in 20-foot gain to take the outright lead at eight under.
Four birdies on the back nine helped Rickie Fowler to a round-of-the-day 67 in tricky conditions to claim a tie for third alongside Casey, with Zach Johnson joining McIlroy a further stroke back.
World No 1 Jason Day posted consecutive gains on the back nine, but will still head in to the final round in the group eight shots off the pace after a level-par 70 at East Lake.
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