A hat-trick from David Goodwillie helped Dundee United seal their place in the Scottish League Cup quarter-finals at Partick Thistle's expense.
The 24-year-old fired home to give United the lead before doubling their advantage before the break.
Substitute Ryan Dow grabbed a third for the hosts after Goodwillie's effort hit the post.
Christie Elliot netted a consolation for Thistle but Goodwillie capped off a resounding victory at the end.
In the all-Scottish Premiership clash it was the visitors who would have been bemused at the half-time score after they had dominated possession for long periods in the first half.
With the game struggling to get into top gear, former Motherwell player Ross Forbes tried his luck from distance with a drive which skipped just past United keeper Radoslaw Cierzniak's left-hand post.
However, Partick lacked an attacker with the predatory instincts demonstrated by the on-loan Blackburn Rovers striker Goodwillie as he latched onto to a slip by Conrad Balatoni.
The Jags stopper cut out a pass from Nadir Ciftci but slipped, allowing Goodwillie to knock the ball past Fox.
The visitors, to their credit, kept plugging away and striker Kris Doolan muscled his way past United defender Calum Butcher but found the angle too tight to get his shot on target.
Thistle were then dealt a hammer blow seconds from the interval.
Fox stretched low down at his right-hand post to save Ciftci's drive but found his good work to be in vain when Goodwillie knocked in from Mark Wilson's corner inside a packed six-yard box.
Thistle pressed for that elusive goal in the second half and Kallum Higginbotham forced a save from Cierzniak with a drive from the edge of the box.
However, United held firm and began to attack sporadically with some menace.
Balatoni cleared Wilson's whipped-in free-kick from just under his own crossbar before Goodwillie failed to get on the end of a dangerous cross from left-back Andrew Robertson.
With five minutes remaining Goodwillie cracked the post with a drive but substitute Dow was on hand to tap into the empty net.
Elliott scored in the final minute for Thistle but there was time for Goodwillie to grab his hat-trick in the first minute of added time after being set up by Stuart Armstrong.
Dundee United manager Jackie McNamara: "I'm delighted. I think we can play a lot better which is the pleasing thing.
"I thought Partick passed the ball well in the first half and they caused us a few problems without really testing our keeper. The pleasing thing for me was scoring four goals and carrying a real threat.
"It was a fantastic hat-trick, especially the last goal. It was great movement from the corner and for David Goodwillie to get a hat-trick is great for his confidence and hopefully that settles him down now and takes the pressure off him.
"It gives us an incredible lift and we'll be doing as well as we can, so we will wait and see in the draw tomorrow."
Partick Thistle boss Alan Archibald : "I thought we knocked the ball about well. We just missed that 'clinical-ness' in front of goal which we have said all season and silly mistakes at the back cost us.
"They got three goals out of nothing and we had to work for our goal.
"In the second half, at 2-0 down, we had a go and they picked us off. I don't think 4-1 is a very fair reflection of the game.
"We know where we are in the finance chain. I don't know what Goodwillie's wages are but I think he's maybe equal to five or six of our players. He is very, very clinical."
- 01 Cierzniak
- 02 Wilson
- 03 Robertson
- 04 Butcher
- 05 Gunning
- 06 Paton (Souttar - 90' )
- 08 Rankin
- 10 Armstrong
- 07 Goodwillie
- 09 Graham (Dow - 51' )
- 11 Ciftci (Gauld - 76' )
- 13 McCallum
- 12 Dillon
- 16 Souttar
- 15 Gauld
- 14 Dow
- 01 Fox
- 02 O'Donnell
- 03 Sinclair
- 06 Balatoni
- 13 De la Vega
- 04 Welsh
- 10 Forbes (Lawless - 65' )
- 14 Elliot Booked
- 20 Kerr Booked
- 23 Higginbotham (Craigen - 76' )
- 09 Doolan (Baird - 51' )
- 12 Gallacher
- 11 Lawless
- 19 Osbourne
- 07 Craigen
- 17 Baird
Live Text Commentary
Full Time The final whistle goes and the game is over.90:00 +2:43
Free kick taken by Scott Fox.90:00 +2:37
The offside flag is raised against Ryan Dow.90:00 +1:53
Christie Elliot takes a shot and cleared the bar.90:00 +0:47
Stuart Armstrong provided the assist for the goal.90:00 +0:47 Goal scored
Goal! - David Goodwillie - Dundee U 4 - 1 Partick David Goodwillie scores with their right foot. Dundee Utd 4-1 Partick.90:00 +0:27
Clearance by John Rankin.90:00 +0:15
Corner taken by Steven Lawless.89:51
Free kick awarded for an unfair challenge on James Craigen by Mark Wilson.89:34 Substitution
Substitution John Souttar on for Paul Paton.88:33 Goal scored
Goal! - Christie Elliot - Dundee U 3 - 1 Partick Christie Elliot scores a right footed goal. Dundee Utd 3-1 Partick.88:22
Free kick taken by Christie Elliot.88:08
Free kick awarded for an unfair challenge on Conrad Balatoni by Ryan Gauld.86:48
Radoslaw Cierzniak restarts play with the free kick.86:43
The assistant referee flags for offside against John Baird.86:12
Assist on the goal came from David Goodwillie.86:12 Goal scored
Goal! - Ryan Dow - Dundee U 3 - 0 Partick Ryan Dow scores with a right foot finish. Dundee Utd 3-0 Partick.85:16
Ryan Dow takes the chance to get an effort at goal. Scott Fox parries the ball away.84:46
David Goodwillie takes the chance to get an effort at goal.82:36
Free kick awarded for a foul by John Rankin on John Baird.
Corner taken by Ryan Dow.82:01
The ball is sent over by Ryan Gauld.80:49
Shot by John Rankin went over the crossbar.80:43
Ryan Gauld restarts play with the free kick.80:31
Unfair challenge on David Goodwillie by Conrad Balatoni results in a free kick.79:26
Andrew Robertson produces a cross.78:53
Shot by James Craigen. Radoslaw Cierzniak catches the ball.78:36
Corner taken by Stephen O'Donnell.78:02
Clearance by Conrad Balatoni.77:53
Corner taken by Mark Wilson from the left by-line.77:38
Clearance made by Conrad Balatoni.77:31
Mark Wilson crosses the ball in from the free kick.77:09
Ryan Dow fouled by Stephen O'Donnell, the ref awards a free kick.76:48
Free kick taken by Mark Wilson.76:35
Free kick awarded for a foul by Sean Welsh on Ryan Gauld.75:36 Substitution
Substitution Ryan Gauld replaces Nadir Ciftci.75:16 Substitution
Substitution Kallum Higginbotham goes off and James Craigen comes on.73:36
Nadir Ciftci takes the chance to get an effort at goal and missed to the right of the goal.72:39
Calum Butcher takes the free kick.72:34 Booking
The referee books Christie Elliot for unsporting behaviour.72:20
Foul by Christie Elliot on John Rankin, free kick awarded.67:36
Mark Wilson restarts play with the free kick.67:18
Foul by Aaron Sinclair on Nadir Ciftci, free kick awarded.66:53
Free kick taken by Kallum Higginbotham.66:45
Gavin Gunning gives away a free kick for an unfair challenge on Kallum Higginbotham.66:27
Header by Kallum Higginbotham goes harmlessly over the bar.65:45
Conrad Balatoni restarts play with the free kick.65:35
Unfair challenge on Aaron Sinclair by Nadir Ciftci results in a free kick.64:18 Substitution
Substitution (Partick) makes a substitution, with Steven Lawless coming on for Ross Forbes.63:30
Clearance made by Gavin Gunning.63:24
Aaron Sinclair crosses the ball.62:53
Conrad Balatoni restarts play with the free kick.62:43
Free kick awarded for an unfair challenge on John Baird by John Rankin.60:45
Free kick crossed by Ross Forbes.60:35
Unfair challenge on Ross Forbes by Mark Wilson results in a free kick.58:57
Kallum Higginbotham takes a weak shot. Radoslaw Cierzniak safely holds on.58:45
Corner from the left by-line taken by Ross Forbes.58:19
Gabriel Piccolo crosses the ball in from the free kick.58:10
Nadir Ciftci challenges Sean Welsh unfairly and gives away a free kick.54:50
Header at goal by Gabriel Piccolo goes over the frame of the goal.54:34
Corner taken by Ross Forbes from the right by-line.51:41
Shot by David Goodwillie went harmlessly over the bar.50:49 Substitution
Substitution John Baird on for Kris Doolan.50:33 Substitution
Substitution (Dundee Utd) makes a substitution, with Ryan Dow coming on for Brian Graham.49:34
Clearance made by Gavin Gunning.49:30
Stephen O'Donnell produces a cross.45:01
The referee blows the whistle to start the second half.45:00 +0:19 Half time
Half Time The referee blows for half time.44:50
Assist on the goal came from Mark Wilson.44:50 Goal scored
Goal! - David Goodwillie - Dundee U 2 - 0 Partick David Goodwillie scores a headed goal. Dundee Utd 2-0 Partick.44:24
Corner taken by Mark Wilson from the left by-line.43:59
Nadir Ciftci takes the chance to get an effort at goal. Scott Fox parries the effort to safety.43:41
Clearance by Stephen O'Donnell.43:28
Free kick taken by Mark Wilson.43:05
Free kick awarded for a foul by Gabriel Piccolo on David Goodwillie.41:31
Clearance made by Calum Butcher.40:55
Corner taken by Ross Forbes.40:30
Kris Doolan has an effort at goal.39:29
Corner from the right by-line taken by Mark Wilson.37:49
Aaron Sinclair takes the free kick.37:42
Unfair challenge on Kallum Higginbotham by Nadir Ciftci results in a free kick.33:55
Clearance made by Gavin Gunning.32:23 Goal scored
Goal! - David Goodwillie - Dundee U 1 - 0 Partick David Goodwillie scores with a right foot finish. Dundee Utd 1-0 Partick.28:24
Corner taken by Mark Wilson.27:42
Brian Graham takes a shot.26:45
Paul Paton makes a clearance.26:37
Corner taken by Ross Forbes.25:40
Scott Fox takes the free kick.25:29
Nadir Ciftci concedes a free kick for a foul on Aaron Sinclair.25:07
Gavin Gunning takes the free kick.24:47
Mark Kerr is cautioned by the ref for unsporting behaviour.24:47 Booking
Mark Kerr challenges Paul Paton unfairly and gives away a free kick.19:16
Ross Forbes takes a shot and went wide of the right hand upright.15:50
Corner taken by Ross Forbes from the left by-line.14:16
Corner taken by Ross Forbes from the right by-line.12:55
Free kick taken by Stuart Armstrong.12:44
Free kick awarded for an unfair challenge on Stuart Armstrong by Sean Welsh.11:40
Brian Graham makes a clearance.11:26
Kallum Higginbotham crosses the ball in from the free kick.11:16
Unfair challenge on Kallum Higginbotham by Paul Paton results in a free kick.8:58
Andrew Robertson manages to make a clearance.8:32
Clearance by Gavin Gunning.6:35
Conrad Balatoni takes the free kick.6:17
Unfair challenge on Kallum Higginbotham by Mark Wilson results in a free kick.4:00
Free kick taken by Radoslaw Cierzniak.3:47
Kris Doolan is ruled offside.3:21
John Rankin makes a clearance.2:26
Corner taken by Ross Forbes from the right by-line.0:55
Corner taken by Ross Forbes.0:00
The referee starts the match.
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