Celtic are shredding Alloa to pieces with their passing as Jota lets fly with a shot that is straight at the keeper.

The League 1 side are looking pretty knackered now as a big gap opens up for Daizen Maeda. David Hutton is out to narrow the angle and the Celtic striker blazes an unconvincing shot wide.

A spot of retribution from Celtic as James McCarthy goes through the back of Mouhamed Niag.

Giorgos Giakoumakis should be celebrating a second goal of the evening but the Celtic striker can only aim a tame header straight at the goalkeeper from close range.

Daizen Maeda is first to a Jota cross from the left but, under pressure, the Celtic striker skews his header from six yards way off target.

The TV cameras focus on the Celtic bench where Yosuke Ideguchi is sitting with a colossal ice pack on his ankle.

Alloa midfielder Mouhamed Niag gets to the ball first but his challenge on Yosuke Ideguchi is very aggressive and the follow through catches the Celtic midfielder high on the ankle.

It looks stomach-churning on the TV replay and that's the evening over for Ideguchi, who limps off to be be replaced by Nir Bitton.

Jota flights a clever cross for Daizen Maeda to run on to. There's no defender near the Celtic striker but his glancing header is brilliantly tipped round the post by David Hutton.

Another Celtic casualty? Liel Abada is in pain and holding his ankle.

Jota is going to come on in the winger's place.

Remember, Celtic lost captain Callum McGregor after a bad head knock in the first half

Liel Abada pings over a cross from the right and it almost sneaks in, with David Hutton clawing the ball away at his near post.

We've got 15 names in the hat for the fifth round of the Scottish Cup and it looks very much like Celtic will be joining them for the draw later this evening.

Here we go for the second half.

Jon Robertson is on for the home side, taking over from Craig Howie.

St Johnstone manager Callum Davidson tells BBC Scotland: “First half was really disappointing, I asked them to do certain things and for the first 30 or 40 minutes, they wouldn’t do any of it.

“Second half, we started to do those things and put them under a bit of pressure, but ultimately if you lose a goal as bad as that you don't deserve to go through.

“I’m really annoyed, that’s probably the best word to say, we gave them an opportunity to get a foothold in the game.

“I think we’re just lacking that confidence at the moment in front of goal. We all know that.”

Kelty Hearts manager Kevin Thomson tells BBC Scotland: "We wanted to compete, I said to the players before the game we weren’t here to make the numbers up.

"We wanted to have a go, we played with three strikers and an attacking midfielder too.

"We knew it would be a difficult game and we had the utmost respect for them. They’re a good full-time team, three divisions above us but at the same time, everybody will know me, if I’m in it, I want to try and win it.

"To a man, I have to say the boys were unbelievable. I’m proud of them, proud of the town, proud of all the supporters that got behind us and I’m over the moon."

The big story of the day is League 2 side Kelty Hearts bundling Scottish Cup holders St Johnstone out of the tournament.

The Perth side had the bulk of play at Central Park but fell to a 10th successive loss after Kallum Higginbotham struck in extra-time.

Giorgos Giakoumakis got the ball rolling for Celtic, ramming home a close-range volley.

Liel Abada has just added an excellent second.

Alloa have been chasing shadows for long spells, but did have one good sight of goal when Connor Sammon's shot was well blocked by Joe Hart.

Image source, SNS

Celtic are taking no chances with Callum McGregor, who is back on his feet and handing over the armband to Joe Hart before trudging off.

The game re-starts, with James McCarthy still getting stripped and ready.

Concern for Celtic as skipper Callum McGregor does down after a clash of heads.

He's getting some lengthy treatment and James McCarthy is warming up.

A big chance for Alloa on a rare foray up the park.

The ball falls nicely for Connor Sammon inside the penalty box but the burly striker can't get his shot past Joe Hart, who spreads himself to block.