United are in poor form, but they have started on the front foot at the moment.

United get the game underway. Will it be a repeat of the St Mirren victory in the Scottish Cup final 30 years ago, or will United win this trophy for the first time?

SPFL chief executive Neil Doncaster: "It's a great occasion. The weather couldn't be better.

"It's a trophy. These are the sorts of days that you remember, actually winning something. We're delighted and I'm sure they're delighted to be here

"Sponsorship market generally in football is tough. Our objective when we looked at revamping both the Betfred Cup and the IRN-BRU Cup was to do something different, to reinvigorate it and to attract attention.

"I think we've done that. The inclusion of the colt teams, that seems to have gone down very well.

"The inclusion of the Northern Irish teams and teams from Wales - we've got the Welsh League here - they're absolutely delighted to be working with other leagues in the UK.

"I think it's been a good success."

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There's a minute silence for the victims of this week's attack at Westminster.

Only the snap of photographers' shutters could be heard.

The teams are out into the Lanarkshire sunshine at Fir Park.

A couple of minutes to kick-off.

Dundee United manager Ray McKinnon on BBC Radio Scotland: "It is an absolutely magnificent day for a cup final and I have good memories of playing here at Fir Park. 

"The players are motivated and we are really looking forward to it. 

"It is not about the league and what we do after this game. 

"We have to be focused and concentrating on winning this game."

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United boss Ray McKinnon makes three changes as he looks to revive his side's form.

Charlie Telfer, 18-year-old Ali Coote, who makes his first start of the season, and Nick Van der Velden come into midfield in place of Lewis Toshney, Thomas Mikkelsen and Frank van der Struijk.

Meanwhile, St Mirren's only change is enforced, with striker John Sutton, who was rested last week, coming into the side in place of the cup-tied Cammy Smith.

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The Challenge Cup is for teams outwith the top flight, so this is only the second time United have competed in the competition - losing to Stenhousemuir in the final back in the 1995-96 season after a penalty shoot-out.

St Mirren have lifted the trophy once - beating Hamilton Accies in the final in season 2005-06.

United lie fourth in the Championship, 17 points ahead of St Mirren.

However, the Buddies beat United 3-2 last week at Paisley 2021 Stadium, are seeking a third straight victory and are unbeaten in their last three games.

In contrast, United are in freefall, have lost three games in a row and are without a win in their last four outings.

St Mirren manager Jack Ross on BBC Radio Scotland: "United have made a few changes, but I expect them to play the system.

"I want to win today and I want to keep us up and I think we can do both.

"It is a stand alone game, but it would do us no harm to win as it would be another big step forward.

"If we carry in the same vein as we have in recent weeks, we will have a great chance."

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We'll have news later of this afternoon's media conference, where Scotland head coach Gordon Strachan will be speaking ahead of tomorrow's vital World Cup qualifier against Slovenia. 

Strachan says his biggest dilemma is choosing a striker between five options - with only Jordan Rhodes playing regular first-team football.

Who would you choose? What would your line-up be?

Give us your thoughts on Twitter and the BBC Sport Scotland Facebook page.

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Dundee United: Bell, Murdoch, Edjenguele, Durnan, Robson, Telfer, Flood, Coote, Andreu, Van der Velden, Murray. 

Substitutes: Dixon, Coll Donaldson, Toshney, Nicholls, Mikkelsen, van der Struijk, Zwick. 

St Mirren: O'Brien, Irvine, MacKenzie, Baird, Eckersley, Magennis, Mallan, McGinn, Morgan, Loy, Sutton. 

Substitutes: Whyte, O'Keefe, Langfield, Demetriou, Webster, Fjelde, Watters. 

Referee: Nick Walsh

It is 30 years since Dundee United faced St Mirren in the Scottish Cup final, with Ian Ferguson's goal handing the Paisley outfit victory in front of 52,000 at Hampden Park.

The two clubs' fortunes have dipped since then and they are both now in the Championship.

Both managers admit that their priorities this season are the second tier, with United still hopeful of promotion and the Buddies sitting bottom of the table and scrambling to avoid relegation.

However, silverware would be welcome, especially if it brought added confidence ahead of the league run-in.

There is no Premiership because it is international week, but there are still some tasty fixtures today in Scotland's domestic football.

Later, there are four Championship games, with Hibernian against Falkirk topping the bill - that's first hosting second in a game Bairns manager Peter Houston admits they can't afford to lose if they are to maintain a title challenge.

There's also a full card in League One and League Two.

However, game of the day is first up at Fir Park, Motherwell, where Dundee United take on Championship rivals St Mirren in the Irn Bru Cup final.

Kick-off is just half an hour away.

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