Veteran former Scotland midfielder Craig Bryson is thrown on by St Johnstone in place of David Wotherspoon.

The 34-year-old was part of a famous cup shock for Clyde over Celtic at the start of his career. Can he inspire another at the other end of his career against the other side of the Old Firm?

Rangers midfielder Joe Aribo is the latest to be booked as he stretches in frustration as a home attack breaks down inside the Saints penalty box.

Scott Wright scored for Rangers against St Johnstone in the league on Wednesday and the former Aberdeen winger replaces Ianis Hagi, with the Romania midfielder having had a subdued performance this evening.

Stephen Robinson
Former Motherwell manager on BBC Sportsound

How close can you go without scoring?

James Tavernier whips in a wonderful dipping cross to the back post and Alfredo Morelos holds off his marker to head towards goal from 10 yards.

However, it deflects off the inside of St Johnstone's far post and bounces into goalkeeper Zander Clark's grateful waiting arms.

Guy Melamed, who lasted 22 minutes before going off with double vision caused by a migraine on Wednesday, leaves the field early again against Rangers.

The Israeli striker has been in good form but is more of a penalty box specialist and manager Callum Davidson adds the strength of Chris Kane to his forward line.

Referee Alan Muir books St Johnstone midfielder Ali McCann for a late challenge on James Tavernier in the build-up to that last Rangers chance.

The yellow cards are mounting up along with the tension and Rangers' pressure.

Zander Clark parries clear at the front post after Glen Kamara plays it to Alfredo Morelos and the Rangers striker fires straight at the goalkeeper at the near post.

Ouch!published at 50mins

50mins

Rangers 0-0 St Johnstone

Joe Aribo receives a bloody nose as the ball bounces off his bonce from Rangers' free-kick into the Saints penalty box.

Zander Clark punches clear from the rebound and the goalkeeper wins a foul for a challenge by Alfredo Morelos but is left clutching an injured arm.

Everyone recovers enough from their ailments to carry on.

Rangers win a free-kick as St Johnstone's Ali McCann almost rips Joe Aribo's shorts off as he is left behind by his fellow midfielder.

Rangers get the second half under way, but who will be in possession of the plaudits - and a place in the Scottish Cup semi-finals - by the end of the game?

Stephen Robinson
Former Motherwell manager on BBC Sportsound

Indeed, in 52 games this season, Rangers have only failed to score twice - once early in the league season against Livingston and then in their Europa League exit at home to Slavia Prague.

Can St Johnstone become the third side to force them to draw a blank?

Tom English
BBC Scotland's chief sports writer

Charlie Adam
Former Rangers midfielder on BBC Sportsound

St Johnstone manager Callum Davidson will be delighted with his side's first-half performance with the score goalless against the Scottish champions.

Rangers have only hit the target twice, but a Glen Kamara shot and an Alfredo Morelos were easily dealt with by goalkeeper Zander Clark.

Meanwhile, the closest to a goal came from the visitors, with Scott Tanser's delightful volley forcing a good save from Allan McGregor.

Still all to play for and still the possibility of a cup upset.

St Johnstone midfielder David Wotherspoon escapes with a yellow card for a wild challenge on Ianis Hagi as we enter first-half stoppage time.