Partick Thistle progressed to the last 16 of the Scottish Cup courtesy of a well deserved win over St Mirren.
The Premiership visitors were totally in command until a late wobble when Keith Watson forced the ball home.
Danny Seaborne shot the Jags ahead on 62 minutes when the ball fell to the defender from a corner.
Thistle's second goal came from another corner, with David Amoo converting after Jamie Langfield had saved a Kris Doolan overhead kick.
The other consistent factor was the quality of the Paisley pitch which laughed off the snow and looked pristine, if with added zip. Is there a better playing surface in all the land?
Thistle tried to prove the point with slick passing and the first real opportunity which took full 20 minutes to arrive saw Stuart Bannigan and Stevie Lawless combine on the break to set up Doolan who came sliding in and should really have scored.
But already we were getting a sense of things to come.
Even the missed chance was costly for Saints. Stuart Carswell was injured in attempting to halt it and managed to stoically play on for a few moments, but had to surrender his place to young Jordan Stewart.
That triggered a reshuffle which was hardly in manager Alex Rae's plans and Thistle went on to dominate the first half with Lawrence Shankland dreadfully isolated up front and the Paisley back line under siege.
Amoo sizzled a shot which Langfield just about dealt and the score was somehow blank at the interval.
There was another alteration in the Buddies' shape but not much changed in the second half. Thistle continued to threaten. Doolan and Amoo both went close again. A goal was coming.
It came when Seaborne got on the end of a Bannigan corner kick on the left which was knocked down by a Saints head.
The defender was given too much time and space and drove the ball beyond Langfield, although the goalie did get a hand on it.
Another corner 10 minutes later, another goal. Doolan met Bannigan's corner with a spectacular bicycle kick which rattled the crossbar after a touch from the goalie and Amoo was there to bundle the rebound over the line.
Thistle were actually coughing nervously as Saints rallied late on and Watson scrambled an 88th minute goal after a couple of late chances, one of which brought a miraculous save from Thomas Cerny.
The match was labelled First foot Friday and the Maryhill faithful enjoyed the party, while the hangover had already bitten on St Mirren.
Full Time Match ends, St. Mirren 1, Partick Thistle 2.
90:00 +2:11 Full timeFull Time Second Half ends, St. Mirren 1, Partick Thistle 2.
89:43Andy Webster (St. Mirren) wins a free kick in the attacking half.
89:43Foul by Sean Welsh (Partick Thistle).
87:52 Goal scoredGoal! Goal! St. Mirren 1, Partick Thistle 2. Keith Watson (St. Mirren) right footed shot from the centre of the box to the high centre of the goal following a corner.
87:52Corner, St. Mirren. Conceded by Liam Lindsay.
87:45Corner, St. Mirren. Conceded by Tomás Cerny.
87:22Attempt saved. Calum Gallagher (St. Mirren) right footed shot from the centre of the box is saved in the top left corner.
87:12Corner, St. Mirren. Conceded by Danny Seaborne.
86:55Attempt blocked. Lawrence Shankland (St. Mirren) right footed shot from the centre of the box is blocked.
86:43Attempt blocked. Scott Agnew (St. Mirren) right footed shot from the centre of the box is blocked.
86:20Corner, St. Mirren. Conceded by Liam Lindsay.
85:49 SubstitutionSubstitution Substitution, Partick Thistle. Kevin Nisbet replaces Kris Doolan.
85:21 BookingBooking Abdul Osman (Partick Thistle) is shown the yellow card for a bad foul.
85:15Stephen Mallan (St. Mirren) wins a free kick in the attacking half.
85:15Foul by Abdul Osman (Partick Thistle).
83:58 BookingBooking Stephen Mallan (St. Mirren) is shown the yellow card for a bad foul.
83:51Foul by Stephen Mallan (St. Mirren).
83:51Sean Welsh (Partick Thistle) wins a free kick in the attacking half.
80:21Keith Watson (St. Mirren) wins a free kick on the left wing.
Foul by David Amoo (Partick Thistle).
79:03Attempt missed. Calum Gallagher (St. Mirren) right footed shot from the right side of the box is high and wide to the left.
77:51Andy Webster (St. Mirren) wins a free kick in the attacking half.
77:51Foul by Kris Doolan (Partick Thistle).
76:51Corner, St. Mirren. Conceded by Abdul Osman.
76:17 SubstitutionSubstitution Substitution, St. Mirren. Steven Thompson replaces Cameron Howieson.
76:04Corner, St. Mirren. Conceded by Danny Seaborne.
72:51 Goal scoredGoal! Goal! St. Mirren 0, Partick Thistle 2. David Amoo (Partick Thistle) right footed shot from the centre of the box to the centre of the goal.
72:51Kris Doolan (Partick Thistle) hits the bar with a left footed shot from a difficult angle on the right.
72:40Corner, Partick Thistle. Conceded by Calum Gallagher.
66:04Attempt missed. Danny Seaborne (Partick Thistle) header from the centre of the box misses to the right following a corner.
65:37Corner, Partick Thistle. Conceded by Andy Webster.
64:04Attempt saved. Liam Lindsay (Partick Thistle) header from the centre of the box is saved in the centre of the goal.
63:49Corner, Partick Thistle. Conceded by Calum Gallagher.
63:17Corner, Partick Thistle. Conceded by Andy Webster.
61:01 Goal scoredGoal! Goal! St. Mirren 0, Partick Thistle 1. Danny Seaborne (Partick Thistle) left footed shot from the centre of the box to the centre of the goal following a corner.
60:58Corner, Partick Thistle. Conceded by Keith Watson.
60:43Attempt blocked. David Amoo (Partick Thistle) right footed shot from the left side of the box is blocked.
59:53Lawrence Shankland (St. Mirren) wins a free kick in the defensive half.
59:53Foul by Liam Lindsay (Partick Thistle).
58:06Foul by Jordan Stewart (St. Mirren).
58:06Sean Welsh (Partick Thistle) wins a free kick on the left wing.
55:18Foul by Cameron Howieson (St. Mirren).
55:18Stuart Bannigan (Partick Thistle) wins a free kick in the defensive half.
54:14Corner, Partick Thistle. Conceded by Scott Agnew.
53:47Foul by Andy Webster (St. Mirren).
53:47Sean Welsh (Partick Thistle) wins a free kick in the attacking half.
53:08Foul by Calum Gallagher (St. Mirren).
53:08Callum Booth (Partick Thistle) wins a free kick on the right wing.
52:05Attempt missed. Kris Doolan (Partick Thistle) left footed shot from outside the box is close, but misses to the left.
49:53Foul by Calum Gallagher (St. Mirren).
49:53Abdul Osman (Partick Thistle) wins a free kick in the attacking half.
45:00Second Half begins St. Mirren 0, Partick Thistle 0.
45:00 SubstitutionSubstitution Substitution, St. Mirren. Calum Gallagher replaces Paul McMullan.
45:00 +2:23 Half timeHalf Time First Half ends, St. Mirren 0, Partick Thistle 0.
45:00 +2:04Foul by Andy Webster (St. Mirren).
45:00 +2:04Danny Seaborne (Partick Thistle) wins a free kick in the attacking half.
45:00 +1:32Paul McMullan (St. Mirren) wins a free kick in the defensive half.
45:00 +1:32Foul by David Amoo (Partick Thistle).
45:00 +0:13Foul by Andy Webster (St. Mirren).
45:00 +0:13Sean Welsh (Partick Thistle) wins a free kick in the defensive half.
43:53Cameron Howieson (St. Mirren) wins a free kick in the attacking half.
43:53Foul by Sean Welsh (Partick Thistle).
42:00Paul McMullan (St. Mirren) wins a free kick in the attacking half.
42:00Foul by Liam Lindsay (Partick Thistle).
41:07Corner, Partick Thistle. Conceded by Keith Watson.
40:51Attempt saved. David Amoo (Partick Thistle) right footed shot from the left side of the box is saved in the centre of the goal.
28:45 SubstitutionSubstitution Substitution, St. Mirren. Jordan Stewart replaces Stuart Carswell because of an injury.
22:00Stephen Mallan (St. Mirren) wins a free kick in the defensive half.
21:58Foul by Abdul Osman (Partick Thistle).
19:32Attempt missed. Kris Doolan (Partick Thistle) left footed shot from the centre of the box is close, but misses to the left.
18:25Jack Baird (St. Mirren) wins a free kick in the attacking half.
18:25Foul by Danny Seaborne (Partick Thistle).
17:38Foul by Andy Webster (St. Mirren).
17:38Kris Doolan (Partick Thistle) wins a free kick in the attacking half.
17:08Foul by Cameron Howieson (St. Mirren).
17:08Gary Miller (Partick Thistle) wins a free kick in the defensive half.
10:37Andy Webster (St. Mirren) wins a free kick on the right wing.
10:37Foul by Sean Welsh (Partick Thistle).
0:00First Half begins.
0:00Lineups are announced and players are warming up.
Live data and text provided by our data suppliers