The hosts take their turn to threaten.

A slack ball out from the back puts Motherwell on the back foot. It's Hartley who is wasteful again, with the ball eventually being worked to Declan McDaid. In the end his shot is harmless, but a warning shot for the Premiership side.

Willie Miller
Former Scotland defender on BBC Sportsound

Mothewell turning the screw here.

Richard Tait cuts a tremendous ball into the box from out on the right. Liam Polworth peels off his man but the Scottish Cup winner's connection is tame, allowing Jack Hamilton to gather. A more solid touch - or perhaps an even softer one - and that's in.

Moments later, James Scott cuts in from the rigth and curls a great shot just wide of the far post.

Err, Motherwell captain Peter Hartley causing problems in his own defence. The centre-half's risky back pass puts Mark Gillespie under pressure to clear, before Hartley then shells a long ball to Dundee.

Less than a minute later, the big defender strides forward and smashes a shot that almost ended up in goal at Tannadice.

Let it not be said that he's not fired up...

A large Motherwell crowd set off pyrotechnics behind the Dundee goal.

Their team have probably started the brightest at Dens, an early corner being headed over. Steady stuff so far from both teams.

Image source, SNS

Scottish Cup holders Celtic are through to the last 16 thanks to goals from Leigh Griffiths and Callum McGregor either side of half-time.

Stuart Bannigan claimed a consolation for Thistle with a stoppage-time penalty.

Celtic's winning streak in domestic cups now stands at 32 games, and Griffiths marked his first start since-mid December by ending his five-month wait for a goal.

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And off we go...

The teams are out the tunnel. Who will win on Tayside?

Thumbs up for Dundee, thumbs down for Motherwell, and just stay quiet for a draw...

Stuart Bennigan pulls one back with the last kick of the game but it's Celtic who progress.

Jeremie Frimpong is penalised for a challenge on Dario Zanatta, who pounced on an awful passback from Christopher Jullien, and the hosts have a spot-kick.

We're into stoppage time with Celtic set to make it 32 successive wins in cup ties. Their aggregate score in that run is 98-11. Impressive stuff.

Since Hibernian's Scottish Cup win in 2016, the baton for the longest wait to regain the trophy has fallen to Dundee. Will this be the start of their run to glory?

Nearly a third goal for the visitors as Odsonne Edouard barrels his way past a couple of defenders then drags a shot inches wide. The ball just won't go in for the French striker tonight.

Celtic then make their second change, with Tom Rogic off for Daniel Arzani to make his first appearance since October 2018.

Pat Bonner
Former Celtic goalkeeper on BBC Sportsound

New Celtic signing Patryk Klimala is on for his debut, the Polish striker replacing goal hero Leigh Griffiths.

Just as Thistle were beginning to believe, their hopes are dashed. Callum McGregor's strike takes a nick off Thomas O'Ware to leave Scott Fox helpless in the Jags goal.

Celtic striker Odsonne Edouard is given far too much space to bring the ball down inside the box and his volley is tipped on to the bar by Scott Fox.

Good hustle from home midfielder Craig Slater down the right wins a corner and leads to a shooting opportunity for Thomas O'Ware, who volleys over. Much more promising from the Championship strugglers.