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A first birdie on the back nine for Dustin Johnson on the 15th and the world number two gets himself back to level par.

American Patrick Reed, who was second overnight on five-under, is just about to tee off alongside South Africa's Branden Grace and South Korea's Byeong Hun An.

At this point in his round yesterday, walking up to the 18th green, Phil Mickelson was on the verge of etching his name once again into the history books.

He needed to make a putt of around 16 feet to card 62 for the day, the best round ever at a major. It didn't drop for the American, but he established a spot at the top of the leaderboard that he is yet to relinquish.

His birdie attempt comes up short again on Friday, but a solid second day is complete for the five-time major champion - who makes 69 for the day, and is 10 under in total.

Hamish: Useful local words for the weather and players:- Dreich = grey, wet & miserable weather. Drookit = soaked and miserable players. 

All applicable today.

Zach Johnson puts everything into that drive and it proves a little too much, his shot kicks on into a bunker at the 15th and the American turns to his caddy with a look of frustration cast across his face - that's about the most emotion we've seen from him all day.

A little bit of work on for the champion to avoid any dropped shots here.

Andrew Johnston finishes with a par and that caps a great finish for the 27-year-old.

Three back-to-back birdies salvaged his round that seemed in danger of collapse with a triple bogey on the 11th.

But he goes into the clubhouse as the leading Englishman and currently tied for seventh.

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Leader Phil Mickelson, following that superb bunker shot, salvages par at the 17th and four on the final hole would see him in the 60s for today's round.

He holds a two-shot lead over Henrik Stenson, who makes par on the 14th and has four to play today.

Former Open champion Ben Curtis had a nightmare 10 at the par-four third on his way to finishing last on 18 over after an 83.

The 39-year-old pulled his tee shot at the 377-yard hole into a deep bunker. He took three to get out and back into the middle of the fairway, from where he then proceeded to dump his approach into a greenside trap.

Curtis' second escape attempt found another bunker a few yards further ahead, from where he splashed out and two-putted.

"It's just one of those things. I should have just chipped out the first time but when you're six over you need to make some birdies," he said.  

"It's typical of the way I've been playing all year. The motivation goes out and at that point you just want to finish."

Image source, AP

Benjamin Watts: Weather at The Open reminding me of school golf tour to Scotland in 2007. One day it rained like this and it really wasn't fun.

John McEnerney: Henrik looking hot if the putter stays hot he'll be in the mix on Sunday. He's the best player that hasn't won a major IMO.

-10: Mickelson (16)

-8: Stenson (13)

-7: Kjeldsen (18), Z Johnson (13)

-6: Bradley (11)

-5: Reed (13:04)

Selected others:

-4: Johnston (17), Garcia (11); -3: Rose (14:04)

-2: Fowler (14:26), McIlroy (14:37); -1: B Watson (14:37)

E: Spieth (14:04), Willett (14:26)

+1: Westwood (16), D Johnson (14); +2: Day (14:26)

Tee times and full leaderboard, external

Well, we said Phil Mickelson might in a spot of bother - a steep bank in front of him and a high lip on that bunker, it looked particularly tricky for a left-hander.

But he flops out of the sand to within several feet of the pin.

Would you rent your house out to Justin Thomas, Jordan Spieth, Rickie Fowler, Jason Dufner, Jimmy Walker and Zach Johnson?

Sounds like a recipe for disaster. Even if all sober, they'd be chipping balls in the back garden, leaving golfing utensils laying around, taking divots in your lawn.

Some brave soul has let their property to the group for the week.

Thomas told reporters the group "were like kids again", adding their chef had "saved them" by cooking American dishes on the eve of The Open.

It seemed to do the trick. Thomas is back out at 12:53 BST and right in the mix.

Phil Mickelson off the tee at the 17th and straight into a bunker full of wet, soggy sand.

Meanwhile, Zach Johnson goes back to seven under with a birdie at the 13th - strong putting from the defending champion.

And it's as if they've all noticed Phil might be in a spot of trouble ahead - Henrik Stenson also reclaims a shot on the leader to go eight under, two strokes off the pace.

A sixth birdie of the day for the Swede.

Iain Carter
BBC Radio 5 live at Royal Troon

My feeling is that the cut will be around three-over, four-over. A lot depends on how much the weather deteriorates in the afternoon, not just the rain but the wind getting up, will make a big difference as well.

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A spot of rain doesn't trouble Beef.

Andrew Johnston has just sunk his third birdie in a row to go to four-under par.

This is a strong finish from the 27-year-old.

A good effort from Mickelson with an optimistic birdie attempt at 16, he would have been delighted had that one dropped.

As it is, par should please the one-time Open champion. That three-shot lead remains in tact.

Ged Scott
BBC Sport at Royal Troon

Chris Wood's participation came to an end late on Thursday when he was forced to withdraw with an injury.

This year's Wentworth PGA champion has a good Open record, having finished tied for fifth as an amateur in his first Open in 2008, then missed out a on a play-off at Turnberry a year later.

But, having slumped to three over after 12 holes, he withdrew, citing a "recurring neck injury", leaving playing partners Mark O'Meara and Yusako Miyazoto to tackle Troon's torrential Friday morning rain as a two-ball.

Phil Mickelson opts to come short of the ditch off the tee on the 16th, as he did during that record-equaling round yesterday.

The American then avoids a handful of bunkers on the par-five. Steady stuff from Phil.

Andrew Johnston, aka Beef, is enjoying himself out there after successive birdies at the 15th and 16th.

He started with a pair of bogeys, and shot a triple bogey at the 11th, but four birdies on the front nine and that back-to-back effort make it six for the day to leave the Englishman on three under.

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Henrik Stenson, a long way back on the 12th, plays out of the rough and gets a favourable kick on to the green.

Zach Johnson pitches his approach a fraction short of the Swede and watches his ball bounce the other way - fine margins.