After a pretty steady few days at Bethpage, some might even say boring, it's all kicking off now.

Danny Willett was moving along nicely to move to two under, but he's just triple bogeyed the ninth to slip back to one over.

The troubles all started when the English golfer found the rough off the tee, then the fairway bunker. Big blow.

Huge drive from Matt Wallace on the dogleg seventh. It feels like he's due another birdie.

If a double at three wasn't bad enough a lost ball means Harold Varner III has had to play his fourth on four out of the long stuff.

Bet he wishes he could've taken a mulligan, three shots back. This could be a big number.

Meanwhile Brooks Koepka has got a look at an eagle putt.

If a double at three wasn't bad enough a lost ball means Harold Varner III has had to play his fourth on four out of the long stuff.

Bet he wishes he could've taken a mulligan, three shots back. This could be a big number.

Drama with the leader's group, but Jordan Spieth is still knocking in the pars. His latest on the seventh comes courtesy of a 25-footer. Impressive stuff.

Take a bow, Matt Wallace.

He finds the rough at the front of the green with his second shot on the sixth. It's a horrible lie on a steep slope, but Wallace chips on and is within a 10ft of the hole.

He keeps his cool and gets it in for par.

Anthony Wall
Two-time European Tour winner on BBC Radio 5 live

This won't be helping Brooks Koepka. He won't like hanging around.

Dustin Johnson is playing Bethpage Black a bit like Nick Faldo plays Muirfield (circa 1987).

He looks in complete control of his game and collects another par. Sir Nick would love that!

Hideki Matsuyama's hopes of winning here look like they are toast, as he takes a double.

Things are going a bit better for Jazz Janewattananond.

He's gone straight down the middle of the par-five fourth and leaves himself with an easy 6ft putt for birdie. Back to five under after his bogey on the first.

Andrew Cotter
BBC Sport commentator

Harold Varner is disappearing fast here. And that's a shame. He's padding down into the tree but there's no spectators so it's just Harold, his caddie and a rules official looking. And Brooks Koepka has just arrived after launching his second to the green.

This is horrible. It's the final round of the PGA Championship and it's the round of Harold Varner's life. Time has been called. Lost ball.

Harold Varner III is in the long stuff at four from the tee. He looks pretty rattled.

He takes an iron but the club face spanners off and he moves from the prairie to the jungle down the left. He'll have a job finding his ball in there!

We've all been there.

Brooks Koepka is totally oblivious to his playing partners woe, landing his second on the dancefloor, before then venturing over to help.

Rory won't like this but amateur golfers will. The Northern Irishman finds the rough on the 15th and with his second shot, he winds up a big 'un and hits it about 20 yards! Whoops.

His third is in the sand. Ouch.

Hold on, if you think that's bad....

"Hey now, come on Matty," is the shout from the New York fans as Matt Wallace takes his tee shot on the sixth.

It hasn't helped much though, his ball's rolled down a hill on the left of the fairway.

Image source, Getty Images

Before the 2009 US Open the area behind the green was changed to make it less likely that shots roll down the steep hill.

Trees behind the green were also removed. So perfect for the recreational golfers among us right?

Andy White: I'd drink expensive gin, eat a lot of pizza, go to the casino and buy a really powerful motorbike. I'd waste the rest.

How would you spend the £1.56m prize money?

Harold Varner III's good start is officially over. A total mare at the third ends in a double which sees him slip seven back from the leader and his playing partner Brooks Koepka.

Welcome to a round with Koepka.

That's a great par for Matt Wallace. Such impressive nerve to hole the 16ft putt.

Iain Carter
BBC Sport golf correspondent at Augusta National

Brooks Koepka is looking to become the first player to win a major wire-to-wire, as in leading on his own at the end of each round, since Jordan Spieth won the 2015 Masters

Some exquisite iron play sets up a birdie chance for Dustin Johnson and he doesn't pass those up.

DJ is on the move.

Matt Wallace misses the green on a blustery fifth hole. He chips on with his third shot and has a tricky putt for par to come.