Paul: Some tentative golf being played by these two leaders the past 12 holes. From the looks of it they are there for the taking if someone from behind can make a real run of it.

Iain Carter
BBC golf correspondent at Augusta National

It is such a capricious pin position (on the second green). All sorts of little subtle borrows around the hole.

That keeps a few of the other players interested right now, the fact that these two haven't been able to capitalise on the par five, which many of the chasing pack have managed to do.

Russell Henley is feeling it, as he takes dead aim at the flag on the par-three fourth and smacks it into the flag, before the ball drops and rolls back to leave a long birdie look.

Oh, you're still wondering what that startling noise was in aid of a few moments ago (see 20:08 entry) aren't you?

Well here it is...

Chile's Mito Pereira, making his Masters debut, will be talking about this shot for years to come.

He holes out on the 13th with his approach for an eagle - which came after a triple bogey on the 12th.

Funny old game...

Justin Rose has one of those semi-anguished/ annoyed looks on his face on the sixth green. His tee shot to the back left gives him a decent look at birdie but his putt slides right at the last. I can understand how he'd be peeved by that.

Shane Lowry steadies the ship with a par after sinking a difficult return putt.

Koepka had birdied this second hole all three times he's played it this week, and it looks like a full house until his birdie putt somehow manages to lip out when it looked in all the way.

Rahm never gives his putt a chance and he makes five on a hole he's birdied twice this week.

If Scottie Scheffler had holed even half of the birdie putts he's given himself this week, he'd be 10 shots clear. He really has been awful on the greens.

Yet another chance goes begging on the seventh.

Matt Fitzpatrick shows him how it's done though.

Shane Lowry is back where he started the round and the Irishman looks mystified.

He can't work the angle with his approach into the green and ends up with a long horrible putt which is then woefully short of gas. The par-saver then stays a little left, he was expecting that to nip back a touch.

While Henley and Spieth make moves, Collin Morikawa slinks back into the shadows.

A par on the third wipes out the birdie on the second and he drops off page one.

Rahm gets more than value for money out of his long bunker shot that flopped up and out but just kept on going and going to move into a makeable distance but it'll have some break on it.

Brooks blasts his effort flatter but it motors beyond the pin and they'll have a putting contest for birdies.

2015 champion Jordan Spieth is motoring around the turn. Three successive birdies on the eighth, ninth and 10th holes have lifted him into the top six.

We said he might be fun to watch today!

Russell Henley is now only four back after he rolls in a birdie putt from downtown on the short third to make it back-to-back birdies and all of a sudden he's creeping up on the top two..

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

"Scheffler was exquisite with his putter last year, but this week he has been, in his words, 'utterly appalling'."

Scottie missed a short birdie look on the par-three sixth but has another chance on the seventh...

Both players are well placed to get the birdie which they should really walk off with after their opening two shots.

Oh dear, Hovland misses his to the right. Just leaked. That's a chance gone.

No messing about from Cantlay, though. Confidently drained and he's clawed back the shot he dropped on the first.

An almighty roar goes across the course... is it from the second green?

If either Viktor Hovland and Patrick Cantlay land their eagle putts it will be.

Hovland lines up way out left and hopes to arc his effort round towards the hole. Not enough gas and it dribbles below hole.

That's given a steer to Patrick Cantlay - and the hole is 90 degrees to his stance.

Better effort but still not bothering the can.

Rahm's in the pine straw at the second and has an age to think about his next move with the group ahead still on the green.

He picks it off clean but it's a low bullet that ducks into the left bunker at the front of the green.

Brooks is on the fairway but he also finds the sand, this time the trap on the right just in front of the flag.

Talk about attacking a pin. Olympic gold medallist Xander Schauffele gives his ball the treatment on the fourth, ripping his iron over the front bunker on the fourth to nail his approach to four feet.

The soft green helps but still. The American deserves a birdie for that and bags one to move up into a tie for fifth.

You've got to take care of the par fives at the Masters, and these two have been brilliant on them this week and they'll be crucial in deciding who wears the Green Jacket.

Koepka has been lethal on the longer holes, going nine under for the 12 par fives so far this week, with an eagle, eight birdies, two pars and a bogey.

Rahm is only one shot worse off at eight under on the par fives - with an eagle, seven birdies, three pars and a bogey.

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This has the line from Hovland on the par-five second - does it have the legs? Not quite, the softer greens leave him quite short.

Still, it's an excellent strike and he's putting for an eagle.

Over to Cantlay.... he takes a line slightly to the left and his ball bounds just inside his playing partner's.

Eagles might be a stretch but both will be fuming if they don't land birdies.