If you're just joining us for the first time this weekend, you may not be aware of the newly-extended par-five 13th.

Augusta officials were clearly peeved by all and sundry smashing driver over the trees down the left and leaving an eight-iron or less into a green protected by a tributary stream of Rae's Creek.

So, they bought a few acres of land off their neighbours and shunted the tee back 35 yards. It doesn't sound like much, but it's made the pros think a little more.

They seem to be hitting more into the area that those of us of a certain vintage will recall - the sort of distance where Sir Nick hit a 2-iron on his way to glory many moons ago.

Jordan Spieth has just pummelled his drive down there, leading Sir Nick to reminisce (not for the first time) about that shot. I bet Spieth's not hitting a 2-iron from there though!

A superb par save started Viktor Hovland's round and he needs another on the fifth... got it!

Nerves of steel. Now, if he could land one of the birdies putts...

Cantlay, meanwhile, escapes with a bogey after going up and down.

Still, his challenge might be over for another year. Two over for the final round and six shots back.

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Solid drives by the leaders on the fifth - and now let's see what Brooks Koepka has got to respond with. He's gone 14 holes without a birdie so really needs one soon as a settler.

Now then Viktor Hovland - can you muscle on the leaders?

Metaphorically, of course, because he wouldn't have a chance literally with Beefy Brooks and Rahmbo.

The smiley Norwegian is straight-faced after a short approach which rolls back onto the lower tray of the tiered fifth green.

That leaves him with what Nick Faldo describes as one of Augusta's "iconically notorious" putts.

At least, he's putting. Patrick Cantlay pulls his THIRD shot - after knocking out of the fairway bunker - left of the green.

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Not a bad effort from Russell Henley to get away with a bogey on the fifth in the end and he slips a shot back to four behind the leaders.

Trish Johnson
Eight-time member of the Team Europe Solheim Cup team

Koepka's not been in this position for quite a while and we know how important the majors are to him.

Rahm is battle ready, there's no doubt about it.

There's going to be a lot of nerves out there.

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Justin Rose is in a spot of bother after finding the pines on the left that split the second and seventh fairways.

He punches his second but can't find any of the gaps that separate the three front bunkers guarding the green and takes a trip into the sand.

It all culminates in a bogey for the Englishman who slips back to three under. One birdie, one bogey from Rose so far. Not exactly fireworks.

Rahm's got the line but he's not hit it, so has to settle for par on the fourth and asking the question to Koepka, who splashed out of the sand nicely and has a par tester.

Which he misses! He barely breaths on it down the hill but it's off line so wanders beyond the hole and he has to tap it in for a bogey and we have a tie at the top of the Masters!

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Jordan Spieth is dry on 12. How many of you recall him dumping two balls in the water in 2016 as England's Danny Willett came from nowhere to steal victory?

Well, not today. Finds the front edge. His heart might have been thumping a little. Good two-putt par from 30 feet.

Phil Mickelson drains a 20 footer to keep climbing. That's a third birdie of the week on one of the most feared holes in golf.

Russell Henley is in the trees on the right of the fifth, and he can only chip out before thinning a third right through the green and off the back of a huge slope.

Work to do just to make a bogey here.

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Both these guys are on the dancefloor on the par-three fourth. Can they execute the moves?

Hovland, who holed out to save par on the first, hasn't landed anything since.

This one whistles by the hole too, but he tidies up the par putt.

Patrick Cantlay doesn't! His birdie putt isn't bad, but he misreads the short one back.

Only 13 birdies all week on the hole known as Flowering Crab Apple and just two today...

Pin high from Rahm on the par-three fourth, but Koepka's slight fade stalls in the air and drops right in the front bunker to short side him and that'll be a naughty escape for him to try and execute when he gets down there.

Both men in their t-shirts now with the sun out and all the memories of those sodden few days are long gone.

Too little too late surely as far as a Patrick Reed charge goes. The American isn't exactly sure where he'd going off the tee and looks relieved when it finds the top section of the green.

Sir Nick Faldo reckons this is "one of the great pin positions in the world of golf," and Reed probably agrees as he rattle in his birdie putt.

Xander Schauffele's view of the leaderboard just becomes a little more distant. He has two long putts for par but leaves his first 10-12 feet shy of the hole and can't tidy up from there.

Iain Carter
BBC golf correspondent at Augusta National

Koepka looks slightly frustrated but there's determination about Rahm as he walks up to the fourth tee. No reaction from Koepka at the replay.

Koepka has one of those putts that there's no way he can leave it short...so he leaves it short!

Rahm rolls in his 10-footer for birdie on the third and the lead is down to just one!

Jordan Spieth is having a ball out in the Augusta sunshine. Barely a cloud in the sky as the American lobs his third on the par-four 11th over the bunker and stops it stone dead for a blow-in par.

Some shot that when you consider there's a huge pond just over the green waiting for anything errant.

He's playing with another former champion in Phil Mickelson and the pair get a tremendous reception as they stroll up the hill to the 12th tee.

Henley doesn't make birdie on the fourth despite hitting the flag, which often leaves you worse off then if you just pitch the ball a couple of feet from the hole.

More birdies chances for Viktor Hovland and Patrick Cantlay on the par-four third.

Beautiful from tee to green again.

Hovland goes first, another left-right break. Looking good... no way! It splits at the last second and misses the right lip.

Cantlay's effort is not quite as confident and never looks like dropping.

As you were.

Koepka pulls out the furniture and has a lash at the third, but it's a bit too high and bounds off left down the hill as a lot of shots do at this short par four.

Rahm is in similar shape and whips in a low chip that grabs on the second bounce and leaves him 10 feet, with Koepka closer in but further away as his wedge settles 12 feet past.