St Mirren 1-2 Partick Thistle
Partick Thistle netted twice from second-half corners as they recorded a thoroughly-deserved 2-1 William Hill Scottish Cup win over St Mirren.
Dan Seaborne and David Amoo found the net following deliveries by Stuart Bannigan as Thistle kicked off the fourth-round action with a convincing victory at the Paisley 2021 Stadium.
Keith Watson scrambled a goal back with two minutes left to set up an exciting finale but Thistle held on.
St Mirren had won two out of three games since Alex Rae was appointed manager but in-form Thistle looked sharper, stronger and far more confident on the ball than their Ladbrokes Championship opponents.
Alan Archibald's men zipped the ball about the wet surface for long spells, although they struggled to get in behind St Mirren for much of the first half.
The St Mirren defence managed to deal with several crosses from impressive Thistle left-back Callum Booth, although they were cut open when Steven Lawless evaded two tackles on a counter-attack and threaded it through for Amoo to help on to Kris Doolan, but the striker was sliding as he stabbed the ball just wide from 12 yards.
St Mirren got even more hemmed in after midfielder Stuart Carswell limped off for 19-year-old Jordan Stewart on the half-hour mark and Jamie Langfield was called on to beat away Amoo's powerful strike after the Thistle winger skipped in between two players.
Backed by a vocal and large travelling support, Thistle stepped up a gear after half-time.
Doolan turned and curled a shot just wide from 18 yards after another good run from Lawless and Amoo had a shot deflected into the side-netting after another break.
The Jags took the lead from the resulting corner in the 62nd minute. The second ball fell for Seaborne 12 yards out and he squeezed a first-time left-footed shot through a crowd of bodies and just over the line despite Langfield getting a hand to it.
Liam Lindsay had a header saved following Bannigan's corner before the visitors scored again from the same source in the 74th minute.
Seaborne headed on the delivery and Doolan hit the underside of the bar with an acrobatic scissors kick before Amoo forced the ball home from close range.
St Mirren refused to fold though and threatened from a series of late corners. Lawrence Shankland and Calum Gallagher were denied by Seaborne's block and an excellent stop by Tomas Cerny, before Watson fired home from close range from the next corner. But it was too little, too late for the hosts.