There's some good scoring happening at Hoylake this morning but not everyone is filling their boots and the most notable casualty so far is Louis Oosthuizen who has dropped two shots in four holes and slips back to four under.
It is now raining at Hoylake. It's far from torrential but players and spectators alike have deployed their umbrellas. McIlroy and Johnson both par the 4th and the status quo for now is preserved.
Charl Schwartzel produceds consecutive birdies on the 4th and 5th and he joins Fowler on eight under.
Charl Schwartzel is on fire. Birdie on the 6th completes his hat-trick and the South African storms into a share of second place with Johnson on nine under.
The pack is circling menacingly around McIlroy. Fowler picks up another shot on the 5th and there are now three players within striking distance of the leader.
Four birdies on the bounce for the slimmed down Darren Clarke and the 2011 champion is four under for the day and the championship.
And speaking for champions, Phil Mickelson is one under for the day and the tournament after 13 holes.
McIlroy birdies the 5th for the third day running to go 12 under. Johnson can only muster a par and the lead goes back to three shots.
So far McIlroy's round after five holes - bogey, par, par, par, birdie - is exactly what he produced on Friday. That resulted ultimately in a six under 66 and he'd undoubtedly settle for that again today.
The McIlroy cushion is reduced to two shots again as Rickie Fowler birdies the 6th. That's a remarkable four birdies in just six holes for the flamboyant American this morning.
Pars apiece for Messrs Johnson and McIlroy on the 6th and it's as you were at the top of the leaderboaad for now.
Schwartzel's hot streak of three consecutive birdies come to an end with an unceremonious bogey on the 7th and he drops to eight under.
After what was a pretty explosive start in terms of scoring at Hoylake this morning, things have quietened down a little bit now...
And to underline that previous point, Rickie Fowler cards a bogey five on the 7th to drop a shot and McIlroy is three clear once again.
Francesco Molinari is not enjoying Day Three of The Open as his title hopes appear to be evaporating. The Italian is three over for the day after six holes and now a modest three under for the tournament.
McIlroy produces his shot of the day so far, sinking a 20 footer on the 7th to save par. Johnson has a tap in for his par and the net result is the Irishman keeps his American rival at bay.
Darren Clarke is playing a blinder. Six birdies (and a bogey!) in his last seven holes and the old stager is five under for the day.
The predicted climatic cataclysm has yet to descend on Hoylake and it actually looks jolly temperate out on the course at the moment.
Dustin Johnson starting to struggle. A bogey on the 7th and finds the bunker with his second shot on the 8th.
Par for McIlroy on the 8th but Johnson misses a six footer for par and drops to seven under, five adrift of his playing partner.
Sergio Garcia moves back into contention with a birdie on the 8th. That's his first birdie on the 8th at the third time of asking. He follows up with a birdie on the par three 9th and he goes to nine under alongside playing partner Rickie Fowler.
Tiger Woods completes his front nine (which was actually the back nine because of the two-tee start) in a two under par 35.
McIlroy makes par on the 9th, landing a tricky eight foot par with aplomb. A third bogey in a row from Dustin Johnson however sees the American drop to six under and his round is beginning to unravel.
Jim Furyk picks up a shot on the 11th and the popular American thrusts himself into the mix at eight under. France's Victor Dubuisson is also in the shakedown after a birdie on the 12th.
Defending champion Phil Mickelson is in the clubhouse after carding a one under par 71. He's one under after three rounds and although his grip on the Claret Jug has definitely slipped, it's been a decent enough day at the office for the American.
Charl Schwartzel bogeys 10 and for now at least the South African slips back down the ranks.