Celtic get the set piece clear at the third attempt and look to break, but Tomoki Iwata gives away a foul.

Bit of a mess between Joe Hart and Liam Scales and it results in Livi winning a corner...

Alistair Johnston clips a ball into the front post and Adam Idah tries to poke it in, but Michael McGovern makes himself big to deny him.

Pat Bonner
Former Celtic goalkeeper on BBC Sportsound

There was a huge space in behind Alistair Johnston and that's where Dan MacKay found himself.

But take nothing away from the finish. He had all the time in the world, but he placed it to perfection.

Image source, SNS

A Paulo Bernardo cross is flicked up into the air and Daizen Maeda meets it with his head.

Over.

Rory Loy
Former Dundee striker on Sportsound

We all know that Daizen Maeda likes to play on the shoulder of the last defender.

He times it to absolute perfection and the ball through to him was magnificent.

Image source, SNS

Rory Loy
Former Dundee striker on Sportsound

It looks like a 4-2-3-1, which I am surprised at, for Livingston. But it will probably be 4-5-1 at times out of possession.

They will possibly never have a better chance to win at Celtic Park with Celtic being without their two best players.

A deep free-kick causes all sorts of problems in the Celtic box and Ayo Obileye smashes the far post with a strike.

The whistle goes in the end. Not sure what for.

A bit of panic in the Celtic defence as a Livi long throw bounces about in the box a bit too long before being cleared.

Nice from Nicolas Kuhn.

A dummy and spin gets him to the bye-line, but his cross is claimed by Livi keeper Michael McGovern.

Part one is under way.

Image source, SNS

The players are out.

Joe Hart captains Celtic today.

Livingston manager David Martindale admits to BBC Scotland "I'm depressed" talking about his team's latest injury problems.

"We probably have a makeshift midfield," he says, explaining that Jason Holt was the latest having "phoned in with a cold yesterday".

Martindale explains that Michael McGovern starts again in the cup as Shamal George's time in goal is being managed after a recent injury.

"Celtic have their own issues as well with Callum McGregor and Cameron Carter-Vickers, possibly their two best players, but for us it seems like a constant flow just now.

"It's been a painful season, but we are 90-120 minutes away from Hampden, so we just take one game at a time."

Image source, SNS

Livingston have never won at Celtic Park in 19 visits.

Today would be a good time to change that for the West Lothian side with a semi-final place up for grabs.

Cameron Carter-Vickers just can't catch a break this season.

Celtic manager Brendan Rodgers tells BBC Scotland the absence of Cameron Carter-Vickers is "precaution really".

"He was due to start and had a light session yesterday and he felt something in his hamstring," he says of the centre-half.

"We did not want to take the risk for him and we hope it is nothing major.

"David Martindale has done a brilliant job with Livingston and we know the type of game it will be.

It will be tight, but we will be looking to play with speed and make it difficult for them."

Image source, SNS

Brendan Rodgers hasn't lost a Scottish Cup game.

A 100% win rate for the Celtic manager in 14 ties.

Let's hear the pre-match thoughts of the man...

While we're on the topic of Mr Warnock's shock exit, we've put together a video looking back at his whirlwind month in charge.

You know the score, press play and enjoy (if you can).