Louis Oosthuizen and Jon Rahm feeling the pressure with their respective tee shots on the 14th and 17th.

Rahm hits a fairway bunker but he's in a better spot than Oosthuizen three holes behind as the South African yells 'fore right'. His ball goes for a little ride on a road then comes to rest in light brush.

The leader leaves himself a testing six-foot par putt - and he gets it.

The South African has nailed a number of clutch par putts today - when others have lost their heads, he has kept his.

Rory McIlroy, from the centre of the 14th fairway, flies a wedge towards the middle of the green. His ball grips and then wanders off to the left.

He's down in Bryson DeChambeau territory there

If Jon Rahm doesn't land that maiden Major tonight, he will have nightmares about the narrow misses with the putter.

He's had a load of looks and, to be fair, none have been easy - but so many have been so close. And it's the same again on 16 as a 25-footer drifts just left.

Rahm swings out an arm in frustration.

What a result for the leader.

"Go. go, go, go," he shouts as his third from heavy rough somehow creeps up to, and clings on to, the edge of the green.

I wouldn't fancy being Bryson DeChambeau's ball as he tees it up on the par-four 14th.

Hang on though, a different approach. Not such a hefty blow and his tee shot is under 300 yards. Crucially though, it's in the middle of the fairway. He pings his second into the guts of the green.

A two-putt par stops the rot. But he needs to go birdie hunting.

Jon Rahm won't know about that Oosthuizen misstep but he could well capitalise on it.

An arrow of a tee shot from the Spaniard, seeking his first Major remember, on to the green of the par three 16th.

What's Louis done here?

Trying to protect his one-shot lead, he goes a bit passive with his second on the par five 13th but it flies wide right into the rough.

Wanted a lay-up and he's had a mess-up.

The eagle putt was not to be, but McIlroy is down for a birdie.

That could be a good start to the comeback... Few others are going in the right direction at Torrey Pines right now.

-5 Oosthuizen (12)

-4 Rahm (15)

-3 English (F)

Selected

-2 Koepka (F), Migliozzi (F), Henley (12)

-1 DeChambeau (13), McIlroy (12)

A very tricky and long downhill putt for Jon Rahm on the 15th.

He will take par for certain but we've seen stranger things happen...

Oh my days, it catches the rim of the hole, circles it and stays out. On the plus side, it would have travelled 10 feet past had it not caught the hole. The Spaniard tidies up for par.

Three holes left. Does he need to make up another shot or will Louis Oosthuizen, one shot ahead, fall back?

"Go!" Rory McIlroy says through gritted teeth as he hits his second shot on the 13th.

And he's absolutely nailed it. Few believers left if the thumbs up on the previous post are anything to go by, but he's got a 30ft putt for eagle there.

Bryson DeChambeau may look back on the 13th hole and point to the slip on the tee that started this catalogue of errors.

But, he has only himself to blame, really. He compounded his error by being too greedy with his second. And added to his woes with his third shot. And then played an awful fourth.

His fifth, for par, is from high above the green. The ball pitches around six feet from the hole but it's not done yet, meandering 30 feet down the green.

The bogey putt takes a look as it sidles by. Double. Four shots gone in three holes. His head must be in bits.

Has McIlroy got any hope of reviving this now? Thumbs up if you still believe.

He's hit a decent tee shot on the 13th and is on the fairway.

Yet again Bryson DeChambeau's muscle is not enough. From deep rough on the 13th, he can't get the elevation needed to lift his ball up and onto the green.

He's had three blows and is now in a bunker about 30 yards short of the green.

"Oh shoot!" exclaims the big man as his fourth shot airmails the 13th green. It comes to rest beside a box of lagers... we'll come back to him for his par chip.

The trouble is, he's not making the putts. Another one slides by. Still five holes left for Rahm though - and we've seen how quickly things can change already.

Jon Rahm is looking like the only man in control of his game of those on the leaderboard right now.

The Spaniard pounds a beauty of an approach into the 14th green to give himself another chance of co-leading for the first time.

-5 Oosthuizen (10)

-4 Rahm (13)

-3 English (F), DeChambeau (12)

Selected:

-2 Migliozzi (F), Koepka (F), Schauffele (15), Morikawa (14)

-1 Casey (16), McIlroy (12)

Koepka's par putt touches the edge of the hole and slides past it on the left.

That's a bogey to finish. No third title yet for Brooks.