|Tour Championship third-round leaderboard|
|-8 D Johnson (US), K Chappell (US); -6 R McIlroy (NI), R Moore (US); -5 H Matsuyama (Jpn); -4 J Dufner (US); -3 C Schwartzel (SA), P Casey (Eng); -2 J Thomas (US)|
Rory McIlroy is two shots behind joint leaders Dustin Johnson and Kevin Chappell after the third round of the Tour Championship in Atlanta.
The Northern Irishman shot a bogey-free four-under 66 while overnight leader Johnson carded a one-under 69 that included a double bogey at 16.
Victory for Johnson would see him secure the $10m (£7.7m) prize money on offer in the FedEx Cup.
McIlroy is also still in with a chance of claiming the season-ending bonus.
Johnson, the US Open champion, had trebled his one-shot overnight lead by the turn thanks to birdies at the fourth, fifth and sixth.
But dropped shots at the 14th and 15th saw his advantage cut before a wayward tee shot at the 16th contributed to two more dropped shots.
McIlroy, meanwhile, continued his good form on the back nine at the East Lake Golf Club with birdies at 13, 16 and 18.
The world number three was joined on six under by American Ryan Moore, who also shot a 66.
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