Partick Thistle manager Ian McCall tells BBC Scotland: "The pitch is the same for both teams, that's pretty obvious. I think the groundsman has done a great job to make it as good as it is. It's not ideal for either team, but you've just got to get on with it.

"It's an opportunity for both teams to get to the next round of the Scottish Cup. I think that's more relevant in terms of where Dundee United are right now than us, but nobody will get an easy game at Firhill and we very much want to get to the last eight.

"Alex Jakubiak has come off the bench to great effect in the last two games and I'm really excited to watch him play."

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Derek Ferguson
Former Rangers and Hamilton midfielder on Sportsound

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Northern Ireland striker Liam Boyce drops to the Hearts bench along with defender Taylor Moore and midfielder Peter Haring.

In come Northern Ireland right-back Michael Smith, midfielder Cammy Devlin and on-loan Brighton & Hove Albion left-back Alex Cochrane following the midweek 2-1 home defeat by Dundee.

Livingston show just one change from the midweek league draw with Ross County, with striker Bruce Anderson replacing Odin Bailey.

Fir Park captain and Scotland full-back Stephen O'Donnell remains on the Motherwell bench after the midweek 2-0 defeat away to Dundee United.

Nathan McGinley, Callum Slattery, Jordan Roberts, and Kaiyne Woolery drop out of the starting XI to join O'Donnell among the replacements.

In come strikers Kevin van Veen and Connor Shields, plus left-back Jake Carroll, while midfielder Mark O'Hara returns from injury for his first start since early November.

Aberdeen have got two back-up goalies today, with newly arrived veteran Craig Samson alongside teenager Jamie Shingler. Gary Woods continues to deputise for the ill Joe Lewis.

Adam Montgomery and midfielder Funso Ojo are reinstated after the 3-2 loss to the wing-back's parent side, Celtic, with Dylan McGeouch and Calvin Ramsay making way.

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It’s a case of if it isn’t broke, don’t fix it for St Mirren boss Jim Goodwin as he opts for the same starting XI that beat St Johnstone in midweek.

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Kelty boss Kevin Thomson makes three changes to his starting line-up from the team that beat Elgin City 4-0 last weekend.

Striker Alfredo Agyeman and defender Scott Hooper are out, along with on-loan defender Daniel Finlayson ineligible against his parent club today.

Ross Philp and Jordon Forster come into the starting XI in Paisley today, with League 2 top scorer, Nathan Austin, also back in Kelty's starting XI.

Thistle make two changes from the midweek 3-3 draw with Inverness Caledonian Thistle.

Defender Tunji Akinola is unavailable and midfielder Cammy Smith drops to the bench.

In comes left-back Stephen Hendrie, while forward Alex Jakubiak makes his first start on loan from Dundee.

United name an unchanged side from the one that beat Motherwell 2-0 in midweek.

They do welcome Charlie Mulgrew back into the squad and the former Scotland defender takes his place on the bench.

Aberdeen have signed goalkeeper Craig Samson, with the 37-year-old named on the bench for the Dons.

Samson retired as a player in 2018 but was signed by Hibs as a coach and registered as a player for the 2020-21 season - although he didn't play.

He will, predominantly, be a goalkeeping coach at Pittodrie due to a knee injury suffered by Gordon Marshall.

However, with first choice Joe Lewis unavailable and youth goalkeeper Tom Ritchie suffering a "serious injury" yesterday afternoon, Samson will also be back-up for Stephen Glass' side.

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Motherwell: Kelly, Ojala, Mugabi, Solholm, Carroll, Donnelly, Goss, O'Hara, Efford, Shields, Van Veen.

Substitutes: Fox, O'Donnell, Lamie, Woolery, Shaw, Slattery, Cornelius, Tierney, Grimshaw, Amaluzor, Roberts.

Aberdeen: Woods, McCrorie, Bates, Gallagher, Montgomery, Ojo, Brown, Ferguson, Besuijen, Hayes, Ramirez.

Substitutes: Samson, Shingler, MacKenzie, Emmanuel-Thomas, Jenks, McGeouch, Ramsay, Barron, Kennedy.

Heart of Midlothian: Gordon, Smith, Kingsley, Souttar, Baningime, Devlin, Halliday, Cochrane, McKay, Simms, Sibbick.

Substitutes: Stewart, Haring, McEneff, Woodburn, Boyce, Mackay-Steven, Atkinson, Moore. Ginnelly, Pollock.

Livingston: Stryjek, Devlin, Fitzwater, Obileye, Penrice, Holt, Omeonga, Pittman, Forrest, Nouble, Anderson.

Substitutes: Maley, Boyes, Longridge, McMillan, Kelly, Montano, Lewis, Sibbald, Shinnie, Bailey, Chukwuemeka.

St Mirren: Alnwick, Fraser, Shaughnessy, Dunne, Tait, Power, Gogic, Ronan, Kiltie, Jones, Greive.

Substitutes: Lyness, Urminsky, McCarthy, Millar, Tanser, Flynn, Erhahon, Henderson, Erwin.

Kelty Hearts: Jamieson, Black, Forster, Cardle, Austin, Barjonas, Higginbotham, Tidser, Philp, Ngwenya, O'Ware.

Substitutes: Donaldson, Reilly, McNab, Biabi, Agyeman, Cameron.

Partick Thistle: Sneddon, McKenna, Hendrie, Holt, Mayo, Crawford, Tiffoney, Bannigan, Graham, Docherty, Jakuniak.

Substitutes: Firth, Turner, Smith, Bell, Murray, MacIver, Stanway.

Dundee United: Siegrist, Smith, McDonald, Niskanen, McNulty, Edwards, Butcher, Levitt, Harkes, Graham, Watt.

Substitutes: Eriksson, Clark, Akinola, McMann, Meekison, Neilson, Mochrie, Macleod, Moore, Cudjoe-Anim, Mulgrew.

Let's get going with the team line-ups...

Here's what we have lined up for you in the Scottish Cup this afternoon.

There's two all-Premiership ties and three lower league sides hoping to upset the big boys.

Sportsound coverage of today's games is just about to begin on BBC Radio Scotland.

Among the pundits joining host Richard Gordon are former Scotland internationals Kenny Miller, Willie Miller, Leanne Crichton, Derek Ferguson and Cammy Bell.

Click the wee window at the top of this page to listen.

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Welcome to last-16 weekend in the Scottish Cup, with five fixtures kicking us off over a staggered afternoon and evening, culminating in Rangers' visit to Annan Athletic, with one Aaron Ramsey due to make his first Light Blues start.

There's also some big games in the Championship and League 1.

So stay with us for the build-up, live commentary and post-match reaction on the website and BBC Radio Scotland's Sportsound.

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