Anything Donegal can do, so can Tyrone! Sean O'Donnell shows some great footwork to make the space and he fires over.

That's a nice bit of quality from Daire O Baoill, as he evades his man and lands a superb point from play.

Philly McMahon
Eight-time All-Ireland winner with Dublin on BBC Sport

The way the teams have set up defensively it will be more of a settled game. The only energy injected is when there's a turnover.

And it's advantage Tyrone once again as Darren McCurry lands another free.

Padraig Hampsey is deemed to have fouled Ciaran Thompson, and Oisin Gallen levels the game once more.

Darragh Canavan is caught by goalkeeper Gavin Mulreany as both challenged for the ball, and the forward dusts himself down to put Tyrone in front.

Darren McCurry lands an easy free to bring the Red Hands level. Nicely done.

The rain has caught everyone so off guard the PA system has asked people to go back to their cars to put their windows up.

More exciting than any on-pitch action so far. Plenty of time for things to improve, however.

Donegal get the first score of the day as Niall O'Donnell pops it between the posts.

We're four minutes into and we're back into the early lull.

In other news, the rain has returned.

It's been a patient start with Tyrone camped in the Donegal half.

Sean O'Donnell bursts the game into life with a lovely jink and twist, but he can't get an effort away.

Image source, Getty Images

Away we go!

Orla Bannon
BBC Sport NI at Celtic Park

Word is Tyrone sent back over 2,000 unsold tickets and they seem to have been snapped up by Donegal fans who are here in huge numbers.

We're almost ready to get under way at Celtic Park. Who do you fancy for this one?

Remember, Armagh await the winner.

Faith Harper
BBC Sport NI at Celtic Park

Celtic Park is a sea of colour with both sets of supporters bringing the noise and atmosphere to this semi-final.

Michael Murphy
Former Donegal captain and All-Ireland winner on BBC Sport

When I was growing up, Donegal and Tyrone always felt like much more than a game.

It's always been a big rivalry in Ulster and I've no doubt this Sunday's Ulster semi-final will be another intense battle.

Tyrone have won the last two championship meetings. Last year, they came to Ballybofey and deservedly beat Donegal to reach the All-Ireland quarter-finals.

The contrast in the mood around Donegal now compared to 12 months ago is obviously stark, but I still don't subscribe to the idea that Donegal are clear favourites to win this weekend.

A lot of people would fancy Donegal because of the win over Derry last week, but I'm expecting a much different type of game in Celtic Park this weekend.

There was so much space in the Derry game and Donegal capitalised. Knowing how that game turned out, Tyrone will take the space away and force Donegal to play a different way.

If they are to beat Tyrone, Donegal may require a more patient, methodical approach than what we saw against Derry.

Image source, BBC Sport

Oisin McConville
Armagh All-Ireland winner on BBC Sport

I expect Donegal to face a real proper challenge from Tyrone today. Tyrone have made a few changes and look stronger - I expect a rip-roaring game.

Matt Gault
BBC Sport NI at Celtic Park

Image source, BBC Sport

I wasn't too optimistic about the weather today as the raindrops clattered off the car on the way up the A6.

It's looking good at the moment but there is rain expected later. Celtic Park might not be as sun splashed as it was for Donegal's win over Derry last week.

Antrim hurler Gerard Walsh, whose sideline cut helped the Saffrons seal a riveting Leinster Championship win over Wexford at Corrigan Park on Saturday, pays tribute to Ryan Straney.

Straney, who hurled for Lamh Dhearg, died in a car crash in Australia earlier this week.

A storming finish saw Antrim grab a magnificent 2-22 to 2-20 victory over Wexford at Corrigan Park on Saturday to get their Leinster Hurling Championship campaign firmly back on track.

Read the report from the game here.

Image source, Inpho