Curtis Main powers a header wide of the near post, but since their goal Motherwell have been second best at Tynecaslte and it was a deserved equaliser for Hearts through Steven MacLean.

Steven Naismtih and Peter Haring had early headers cleared off the line, while Naismith should have scored with a close-range header.

Image source, SNS

Brian McLauchlin
BBC Sport Scotland

This game is very similar to last nights quarter-final at Easter Road with one major but important difference, GOALS!

The game is raging from end to end and the conditions are definitely playing their part with the greasy surface making it difficult to control the ball.

Image source, SNS

Steven Naismith should score for Hearts, but he cannot keep his header down from close range.

Motherwell have barely kicked the ball in the past 20 minutes - the half-time whistle cannot come soon enough for them.

Hearts are flying at the moment. It has been all them since Motherwell took the lead - Curtis Main's chance apart - and it was a deserved equaliser.

But for Gael Bigirimana, he is having a poor game - certainly by his standards - for Motherwell. Stephen Robinson's men need to see more from him.

Zander Clark's punch on Leigh Griffiths' corner is unconvincing but the visitors cannot capitalise.

Celtic soon win another corner on the other side, the left, and Griffiths' delivery is headed over by Mikael Lustig.

Paul Hartley
Former Celtic and Scotland midfielder on BBC Radio Scotland

St Johnstone will be feeling pretty comfortable. Celtic haven't really cut through them. They need to get Drey Wright on the ball a bit more - he looks like the one player that can cause Celtic problems.

Allan Preston
BBC Scotland summariser

Stephen Robinson will be furious with Gael Bigirimana - he had the ball in his own box, takes a touch, loses it to a great Arnaud Djoum tackle. Callumn Morrison whips it in, Steven Naismith heads it back across goal and Steven MacLean, who scored a hat-trick against Motherwell on his very last St Johnstone game, scores.

Better play from Hearts. Olly Lee is trying to make something happen, the ball is rolled out to Callumn Morrison, the ball is squared to Steven MacLean who sends the ball just over.

At the other end Curtis Main almost makes it 2-0 after beating the offside trap, but Hearts goalkeeper Zdenek Zlamal pulls off a great save.

Image source, SNS

Celtic's Kristoffer Ajer is struggling after pulling up on the McDiarmid Park turf. He makes way for Jack Hendry.

Billy Dodds
Former Scotland striker on Sportsound

Joe Shaughnessy is ball-watching at the back post. It's a brilliant pinpoint ball from Edouard and Griffiths should have scored from point-blank range.

Zander Clark uses his feet to stop Leigh Griffiths' header after the Celtic striker gets away from Joe Shaughnessy.

Hearts are winning a few corners as they try to get themselves back on level terms. They have already had one effort cleared off the line through that route.

Brian McLauchlin
BBC Sport Scotland at Thnecastle

Motherwell look like a team on a mission at Tynecastle with Stephen Robinson’s players firing into tackles and ensuring the Hearts players don’t get an easy time on the ball.

The goal has certainly given them huge confidence - Curtis Main burying a penalty after Jimmy Dunne's handball. But the game is being played at a crazy pace with the damp conditions along with the gusting wind making it extremely difficult for players to control the ball.

Image source, SNS

Paul Hartley
Former Scotland and Celtic midfielder on Sportsound

Celtic are just passing from side to side, it's pretty easy for St Johnstone to deal with. They've got everybody behind the ball and they're forcing Celtic into mistakes.

Image source, SNS

A tense opening 20 minutes in Perth with little in the way of chances. The teams are battling not only each other but the conditions with the wet weather clearly evident.