Match ends, St. Mirren 1, Dundee United 2.
St Mirren 1-2 Dundee United: 10-man visitors hang on to beat top-flight hosts
Championship side Dundee United progressed into the quarter finals of the Scottish Cup for the first time in three seasons after beating St Mirren.
Pavol Safranko redirected a Peter Pawlett shot past Vaclav Hladky before Nicky Clark lobbed in a second.
But they had Callum Butcher dismissed for a high challenge on Ryan Flynn.
And that galvanised St Mirren, for whom Mihai Popescu hit the bar before Duckens Nazon's deflected strike set up a nervy conclusion.
Oran Kearney's side could not repeat their feat of coming from 2-0 down against Championship Alloa Athletic in the last round - which is one of just three wins in their last 27 games - and now only have a fight for Premiership survival in their agenda.
Encouragement for United
If there was a discernible gap between the bottom of the Premiership and the top end of Championship, it was in United's favour....until the red card.
Kearney's hitherto disjointed team were roused by that - and the interval introduction of Kyle McAllister and Simeon Jackson - but lacked the guile to cleave open United defence more than once.
But for the boisterous, 1500-strong United support, the performance was further encouragement that this expensively-assembled team can perhaps escape the second tier at the third attempt.
'Our first-half performance was terrible' - reaction
St Mirren manager Oran Kearney: "I'm disappointed we're out. I asked players to learn from the last round and not give teams a head start. To be honest, our first half performance was terrible, it was embarrassing, probably the worst since I've been here.
"Football lasts 90 minutes. At any level, that's not good enough. Lack of a performance in the first half has been the problem and that's what cost us in the cup."
Dundee United head coach Robbie Neilson: "I'm delighted the way we controlled the game. When you're down to 10 men its always going to be difficult, but they never caused us any real problems. I thought it was quite comfortable.
"Our sending off was definitely a red card, but the one before that was a disgrace and the referee saw it. Paul McGinn takes Cammy Smith right out on the chin. The fourth official saw it, the referee saw it, I'm going to have a word with John Fleming [SFA head of refereeing] tonight to get an answer. The referee is four or five yards out - why then he doesn't make the decision I don't know."
- 2McGinnBooked at 58mins
- 28MacPhersonSubstituted forErhahonat 81'minutes
- 22TanseySubstituted forMcAllisterat 45'minutesBooked at 83mins
- 10DreyerSubstituted forJacksonat 45'minutes
- 18ButcherBooked at 62mins
- 25SmithBooked at 59minsSubstituted forSowat 63'minutes
- 10ClarkSubstituted forGomisat 65'minutes
- William Collum
- Shots on Target
Second Half ends, St. Mirren 1, Dundee United 2.
Jack Baird (St. Mirren) wins a free kick on the left wing.
Foul by Peter Pawlett (Dundee United).
Attempt missed. Kyle McAllister (St. Mirren) left footed shot from outside the box misses to the left.
Foul by Mihai Popescu (St. Mirren).
Ian Harkes (Dundee United) wins a free kick on the left wing.
Corner, Dundee United. Conceded by Václav Hladky.
Attempt saved. Osman Sow (Dundee United) left footed shot from outside the box is saved in the centre of the goal.
Attempt saved. Mihai Popescu (St. Mirren) header from the left side of the box is saved in the top centre of the goal.
Kyle McAllister (St. Mirren) wins a free kick on the left wing.
Foul by Jamie Robson (Dundee United).
Kyle McAllister (St. Mirren) is shown the yellow card for a bad foul.
Foul by Kyle McAllister (St. Mirren).
Peter Pawlett (Dundee United) wins a free kick in the attacking half.
Substitution, St. Mirren. Ethan Erhahon replaces Cameron MacPherson.
Attempt saved. Kyle McAllister (St. Mirren) left footed shot from outside the box is saved in the centre of the goal.
Goal! St. Mirren 1, Dundee United 2. Duckens Nazon (St. Mirren) right footed shot from outside the box to the bottom left corner.
Attempt saved. Cameron MacPherson (St. Mirren) right footed shot from outside the box is saved in the centre of the goal.
Corner, St. Mirren. Conceded by Charlie Seaman.