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Barisic with only goal after Sakala hits upright
Hamilton beat Ross County, St Mirren overcome Dundee & Partick Thistle beat Dunfermline - all on penalties
Kilmarnock strike late against League 2 Dumbarton; Livingston beat Stenhousemuir; Motherwell win at Arbroath; Dundee Utd overcome University of Stirling
Last 16 draw is on Sunday
St Johnstone 0-1 Rangers
Remi Matthews is at it again.
A lovely touch and turn from Scott Wright opens up a gap on the edge of the box. The substitute digs out a curling effort, but the St Johnstone goalie claws it away.
St Johnstone 0-1 Rangers
Rangers are trying to turn the screw here.
The visitors work the ball well and it eventually finds its way to Ryan Jack 20-odd yards out. The midfielder takes a touch, but drags his shot a couple of feet wide.
St Johnstone 0-1 Rangers
And here come those changes. Nicky Clark and Theo Bair are on, with Stevie May and Melker Hallberg off.
Rangers make two substitutes, too. Fashion Sakala and Malik Tillman make way, Scott Wright and Glen Kamara are on.
St Johnstone 0-1 Rangers
The flow of traffic is continuing towards Matthews' goal. Andrew Considine manages to divert an in-rushing Fashion Sakala away in a latest charge.
Do St Johnstone need to change something up here?
St Johnstone 0-1 Rangers
Allan Preston
Former St Johnstone defender on BBC Sportsound
Quote MessageIt's a wonderful save. That's going right in the top corner. It keeps St Johnstone in it
Image source, snsSt Johnstone 0-1 Rangers
Remi Matthews has just kept St Johnstone's Scottish Cup hopes alive.
The corner is swung in perfectly on to the head of Connor Goldson. The big Rangers centre-half scuds a header towards the top corner, but Matthews is there to claw it away.
Jeezy peeps, man.
St Johnstone 0-1 Rangers
Martin Dowden
BBC Sport Scotland at McDiarmid Park
Borna Barisic has come in for some criticism of late given some patchy performances. The goal he produced though was real quality and a reminder of the ability he clearly possesses.
Rangers need to see it more often, but it came at a vital moment.
St Johnstone's main aim in this second half is to give Rangers something to think about. They've lacked threat despite competing well but need to muster something positive quickly.
Image source, SNSSt Johnstone 0-1 Rangers
Composure seems to be St Johnstone's issue at the start of this second half.
There's some nice passages of play from the Perth side, but it all seems a bit jittery with the ball eventually being surrendered. Callum Davidson will be looking for his team to calm down a wee bit.
St Johnstone 0-1 Rangers
Allan Preston
Former St Johnstone defender on BBC Sportsound
Quote MessageRangers got a bit of luck, with the ball bouncing into the path of Barisic for the goal. St Johnstone only need a bit of luck to get back into this game, but they need to do something different in this second half
St Johnstone 0-1 Rangers
And off we go again...
Right troops, what we thinking the second half? Do St Johnstone have it in them for a come back?
Thumbs up for St Johnstone, thumbs down for Rangers, sit in silence for extra time...
FT: Arbroath 0-2 Motherwell
"It was a good 90 minutes for us. The first goal settled us," said Motherwell boss Steven Hammell to BBC Sportsound.
"We could have scored one or two more in similar positions, but it was pleasing. The kind of game it was, we minimised their chances.
"A lot of people looked at this and thought this game could have been an upset.
"Even when we were coming off the bus there were still fans there. That made the players, especially the new ones, just what this means.
"It's not surprising."
Image source, SNSFT: Kilmarnock 1-0 Dumbarton
Kilmarnock manager Derek McInnes: "I'm delighted to get through. It was a tough game. We expected that. The credit goes to Dumbarton. They were well set-up. They play very compact: 4-1-4-1. We didn't play well enough or with enough tempo.
"I thought we were knocking on the door before the goal came. Dumbarton were a credit to their division. We knew we'd have our work cut out. It was our fourth game in a tough period. I thought we were a wee bit disjointed today, but I have to credit my players because they kept going and it was a moment of real quality from Jordan.
"I've played Dumbarton three times as manager in the cup, twice at Pittodrie. 1-0, [Adam] Rooney, 1-0 [Sam] Cosgrove and now it's 1-0 Jones here. We have a high regard for Stevie [Farrell] and his team. Hopefully the draw can be kind to us."
Image source, SNSKilmarnock manager Derek McInnes had some nervous moments against Dumbarton
A superb finish from Borna Barisic - the full-back's first-ever Rangers goal from open play - has the holders ahead at the break.
St Johnstone have given as good as they got in that first half, but they have much to do if they are not to fall at this hurdle for the second season running since their own famous lifting of the trophy.
Image source, SNSSt Johnstone 0-1 Rangers
Neil McCann
Former Rangers winger on BBC Sportsound
Quote MessageWhen it comes to Barisic, he almost has no right to hit it that first-time on this surface. But he doesn't just hit it with his laces, he almost hits it with his instep. It is an incredible finish from the full-back
Borna Barisic
What. A. Strike.
Fashion Sakala cuts in from the right before thudding a low shot off the far post.
With the crowd still on their feet, Borna Barisic thrusts on to the ball as it spins back out, absolutely thundering it back across goal into the far corner.
Image source, SNSJames Brown is now on his feet, but he's got a pad on his eye masking what looks like a cut and a swollen face. That's going to sting.
It looks like his race has been run for the day. On comes Graham Carey.
St Johnstone 0-0 Rangers
Worrying scenes for St Johnstone as James Brown is down receiving treatment. The Englishman seemed to take a clatter attempting to clear a corner.
Image source, SNSSt Johnstone 0-0 Rangers
Neil McCann
Former Rangers winger on BBC Sportsound
Quote MessageThere's a wee battle going on between Sakala and Montgomery and they are pointing at each other's faces. Montgomery's a young guy and Sakala just has to match it
St Johnstone 0-0 Rangers
The 400-odd St Johnstone fans all gasp at once.
Borna Barisic whips a delicious free-kick over the home wall with his left foot from 25 yards. It's dipping wickedly, only to drift just wide of the post.
Are we going to get a first-half goal here?