Postpublished at 00:29 British Summer Time 10 August 2014
Righto, that's us for the night. Night.
Leaders: -13 McIlroy; -12 Wiesberger; -11 Fowler; -10 Mickelson, Day
-9 Oosthuizen, Ilonen, Stenson, Palmer
-8 Donaldson, DeLaet, Stricker
-7 Westwood, Chappell, Mahan, Scott, Furyk, Luiten
Jonathan Jurejko, Ben Dirs and Luke Reddy
Righto, that's us for the night. Night.
Rory McIlroy on his round of 67: "It really was a gutsy performance. I felt like every time I made a birdie I made a bogey. But I'm really happy with how I finished again, it was really strong and it puts me in a great position.
"I knew there were guys ahead of me making birdies and it gives me a lot of confidence knowing that if I get challenged and people put the pressure on I am able to respond like I did today. If I can keep playing well and staying mentally strong, there is another major to maybe come my way."
Rickie Fowler, -11 and two off the lead: "That was a good, clean, solid Saturday. I had a good sense of the speed today on the greens and I felt in control of the swing. It'll be fun tomorrow."
Jay Townsend
Former European Tour golfer on BBC Radio 5 live
McIlroy is the class of the field. We've said several times this week he should win. If he plays well he should win. If he plays his best he should win by five or six.
There are only three par fives on this Valhalla course and they will likely prove vital in deciding who lands the bounty.
Rory McIlroy is six under par for his nine attempts so far. Bern Wiesberger is level par for the par five drags and Rickie fowler is -7.
That was some day's golf - and tomorrow promises to be an absolute ripsnorter. There are 18 players within six shots of the lead, there will be bullets flying all over the place tomorrow until there is one man standing. McIlroy and Wiesberger will be the final group out, with Fowler and Mickelson up ahead of them. Europeans in the mix, other than the leading two, are Nordic pair Henrik Stenson and Mikko Ilonen (-9), Wales' Jamie Donaldson (-8) and England's Lee Westwood (-7).
Jay Townsend
Former European Tour golfer on BBC Radio 5 live
That was Tiger-esque from Rory. He didn't play that well and he's got a one-shot lead.
McIlroy to putt first - IN! That's the outright lead heading into the final day, courtesy of a round of 67. The Northern Irishman is one ahead of Austria's Bernd Wiesberger, with whom he'll play on Sunday. Day prods his birdie putt home, moves to -10 courtesy of a round of 69.
Bernd Wiesberger reacts to his round of 65: "It's huge. I felt really well out there, really calm and I hit a great tee shot on the first which calmed the nerves. I'm really proud of how I put myself into this competition. I know I belong out there with the guys and can compete."
Wiesberger carded three successive birdies to close and finish on 12 under.
The most remarkable part about Wiesberger's performance so far this week is that his birdie at 18 today was his first on the par fives. Here's McIlroy from the sand and he's got a makeable birdie putt. Day's escape is a touch closer, both have six or seven footers for birdie...
Day finds the bunker front right with his second at 18, here's Rory... same again, but they've both got plenty of green to work with.
Here's Palmer with that saver and it's a doozy, the man from Amarillo is in with a 69 for nine under par and a tie for fifth. Furyk makes par at the last for a disappointing 72 and seven under overall, he got a bit creaky down the stretch.
It's all gone wrong for Ryan Palmer on 18 - he muffs his first chip from the fluff, meaning he's still got plenty of work to do to save par. Here he is again... races it seven feet past, got a knee-knocker for par....
Austrian Bernd Wiesberger, with no major pedigree to speak of, has two second-place finishes in 2014 on the European Tour. Could Sunday at Valhalla be third time lucky this season?
The Austrian is level with Rory McIlroy on -12, with the Open champion on the par-five 18th.
Day and McIlroy don't mess about on the 18th tee, both high and mighty and straight...
Not a pleasant shot for Palmer, feet on the edge of a bunker, ball above the feet, and he sprays a hybrid right of the green. In case you were wondering what happened to Jim Furyk, he bogeyed 15 and 16 and is the only man not under par today out of the top 40-odd players. That said, he's still seven under.
Ilonen can only make five at the last but that's a 69 to go with a 67 and a 68 and the Finn is nine under. Day makes par at 17, stays nine under. McIlroy putting uphill, left to right, from about 25 feet. Leaves it a couple of feet left but stays joint leader on -12.
Fowler's longun on 18 comes up a couple of revolutions short but that's a birdie for a round of 67 and 11 under. Fowler is looking to make it four top-five finishes in the majors this season.
Day with 158 yards left at 17 and that's pretty ordinary from where he was. McIlroy is in sand out left but that's a peach of an escape, middle of the green.
Palmer chipping on at 17, leaves it five feet short... leaves his par putt a shade right, drops to -9. Fowler with his second on 18, ball below the feet... terrific effort, he's got a longun for eagle and a share of the lead...