Players will start in threesomes on the first and 10th tees, with the first group out at 7:30 a.m.
Masters champions are roughly aligned with Dylan Thomas when it comes to the dying of the light. McIlroy played the par 5s in even - two bogeys, one par and an eagle on No. 8 that got him under par, but only briefly.
Woods hopped out of the way, winced and repeatedly flexed his ankle, and then poured in another putt.
Webb Simpson, who moved into contention after shooting an 8-under 64 that leaves him at 9 under, is hoping for weather to make an impact.
American Patrick Cantlay had set the clubhouse target on six under after a brilliant 64, just one shot outside the course record, while compatriot Tony Finau followed four birdies in the first six holes with a tap-in eagle on the eighth to vault into the lead. There could be several low scores at Augusta National today. Day fired 67 after tweaking his back Thursday.
Four-time victor Woods rolled in a 7-foot birdie putt at the 16th, sending roars cascading across Augusta National as he moved to 11-under for the tournament. He moved up 43 spots on the leaderboard after beginning the day in a tie for 50th.
2 p.m Three-time Masters victor Phil Mickelson began his third round with a par on No. 1.The 48-year-old Mickelson started Saturday three shots behind the leaders on a crowded leaderboard that includes a five-way tie for first place.
"Look, tomorrow is a very important day because there's no doubt someone in the top 15, or a few of them, are going to play very well", Scott said.
On the par three 16th Woods hit a superb tee shot - the closest to the hard pin to that stage of the round. He sent his tee shot on No. 2 way to the right and into the trees, setting off a tough chain of shots that eventually resulted in a double bogey.He recovered with a birdie on No. 3, but the inconsistent play has kept him away from the top of the leaderboard.
That birdie took Woods to six-under, within range of Australia's clubhouse leaders Adam Scott and Jason Day, who are alongside British Open victor Francesco Molinari, three-time major victor Brooks Koepka and Open champion Louis Oosthuizen, at seven-under par.
Tiger Woods of the US hits off the 18th tee during second round play.