Golf's definitely a game of highs and lows as Jon Rahm is finding out again.

The Spaniard decides to go pin hunting on the fifth but Europe's second shot doesn't carry the drink. Not sure he can quite believe that.

Jordan Spieth's second is coming up out of bunker down the right. The American duo have the edge here.

Andrew Priestley: The Ryder Cup doesn’t officially start until someone chips in!

That’ll do from Rahm! We’re under way.

Iain Carter
Golf commentator on BBC Radio 5 Live

An outrageous birdie there at the fourth with a monster putt from Jon Rahm, and Europe move ahead for the first time!

That is a big moment - those kind of things can give you real momentum.

S.E.N.S.A.T.I.O.N.A.L.

Jon Rahm has a putt to win the fourth hole for Europe from the front edge. Surely not he's in a different zip code from the flag from there some 40 feet or more away.

The Spaniard gives it plenty of welly.....go on, go on... It finds the heart of the cup.

Europe have been in trouble on the par-five second and the hosts duly take advantage with a birdie to take the lead.

There's been a lot of talk about Brooks Koepka's feelings towards the Ryder Cup in the build-up this week, but the four-time major winner looks dialled-in out there.

Kat Downes
Commentator on BBC 5 Live

The last bit of red on the leaderboard is extinguished with a birdie from Paul Casey & Viktor Hovland.

That initial flurry of red is gone - all square in all three matches and th fourth underway.

Europe win the third!

Dustin Johnson slides his birdie putt by on the left, but Viktor Hovland's catches the right corner of the cup and drops!

We're all tied up again! Hovland may be making his debut, but he looks to have settled in right away out there.

Jonathan Jurejko
BBC Sport at Whistling Straits

Among all the Stars and Stripes there is solitary Northern Ireland flag hanging over the side of the stand. Wonder if Rory McIlroy spotted it? Perhaps he's brought it...

Once Cantlay nails his tee shot, there is a sound of stomping of feet as the 3,500 leave the first-tee grandstand and head out for their preferred spot on the course.

Ian Poulter is just lapping up all the attention and boos. And responds by booming his tee shot down the middle of the first fairway.

Patrick Cantlay's comes to a stop of the first cut of grass to the left of the fairway. He'll take that on his debut.

Friday's final foursomes match about to get started.

Rory McIlroy and Ian Poulter, who first played together at Medinah in 2012, have just strolled on to the first tee.

They are up against FedEx Cup winner Patrick Cantlay and Olympic champion Xander Schauffele. This should be a cracker.

Extra-loud boos for Poulter from the home fans. I'm sure he probably expected that from the way he is giggling.

Kat Downes
Commentator on BBC 5 Live

Absolutely glorious from Paul Casey - sidles by a foot from the hole and and it comes to rest three feet past.

Viktor Hovland nearly holes out for eagle on the par-five second! It's a guaranteed birdie for Europe, but the Americans respond with a birdie of their own to keep their noses in front.

At the par-three third, Collin Morikawa sticks it in close for another birdie putt.

What can Paul Casey do? He gets it inside the American ball, that's what he can do! What a shot! Two very makeable birdie putts coming up.

Iain Carter
Golf commentator on BBC Radio 5 Live

Seeing the tee-shot from Jordan Spieth at the 489-yard fourth hole. John Rahm is into the rough on the left hand side. Spieth finds that rough there as well.

But the lie for both is possibly not too bad.

What is it about the rough and these tee shots. Jon Rahm gets that all wrong on the fourth putting Sergio Garcia in a spot of bother in the rough.

Jordan Spieth now up. That looks a beauty but them tumbles away down the left slope into the first cut off the fairway.

Daniel Berger misses his birdie attempt, leaving Lee Westwood with a great opening to go 1UP at the first time of asking.

But it slides by on the right! Opportunity missed there.

Jonathan Jurejko
BBC Sport at Whistling Straits

Image source, BBC Sport

One group left and there is still time to ensure that the putting is bang on point.

Just behind the first tee, Ian Poulter and Patrick Cantlay are knocking some balls around on the putting green.

Great putt. Sergio Garcia knocks on and Jon Rahm sinks a tricky left-to-right putt from 10 feet or so to draw Europe level on the par-three third hole.

Normally Jordan Spieth would have been happy rolling down to a few inches from 20 feet or so. Not today.

Brooks Koepka and Matt Fitzpatrick both flick their wedge shots in close at the opening hole.

The Americans are 16 feet away while Europe have only five for a birdie.

High-quality golf on display early doors here.

Lee Westwood equals Sir Nick Faldo's record of 11 Ryder Cup appearances.

Jonathan Jurejko
BBC Sport at Whistling Straits

"Come on Daniel-san," shouts one guy before Berger lashes his drive down the fairway.

Didn't sound like Mr. Miyagi.

(If you haven't seen Karate Kid - and why not? - then this is lost on you...)