Dani Lopez scored a hat-trick as Stevenage thrashed League One promotion chasers Sheffield United.
Lopez, who was only recalled from a loan spell at Barnet earlier this week, put the hosts ahead when he turned Neill Collins inside the box.
Gavin Mahon played Lopez through for 2-0 and the Spanish striker completed his treble from the edge of the box.
Lucas Akins added a fourth with an individual effort to condemn the Blades to their first defeat in eight games.
United are four points behind leaders Doncaster but have a game in hand.
VIEWS FROM THE DRESSING ROOM
Stevenage manager Gary Smith told BBC Three Counties Radio:
"It's a wonderful result, and of course Dani Lopez's performance will make the headlines and rightly so.
"Today was really the highlight of the season at home - terrific result and a great performance, four goals and a clean sheet.
"We've seen today that he [Lopez] has got bundles of ability, he's got two very good feet. And if you can get him in and around that penalty area what he will do is he'll work an angle and get a shot off.
"Today, the creative side of the game has looked a hell of a lot better."
Sheffield United manager Danny Wilson told BBC Radio Sheffield:
"I have to say we've saved all of our mistakes for one game. Defensively we were massively second best all the game.
"We've allowed too much space in all four goals and very, very poor goals I'll have to say.
"Throughout the game we were second best in too many areas and that's cost us the game."
Live Text Commentary
Full Time The game is over, as the referee blows his whistle.90:00 +2:40
The assistant referee signals for offside against Anthony Grant. Indirect free kick taken by George Long.90:00 +2:01
Outswinging corner taken left-footed by Barry Robson played to the near post, clearance by Greg Tansey.90:00 +1:11
Sam Hoskins is flagged offside by the assistant referee. Free kick taken by George Long.86:51
Inswinging corner taken left-footed by Barry Robson, Steve Arnold makes a save.85:01
Unfair challenge on Barry Robson by James Dunne results in a free kick. Direct free kick taken by Tony McMahon.85:01 Substitution
Substitution Sam Hoskins comes on in place of Lucas Akins.84:34
Tony McMahon takes a shot. Blocked by Mark Roberts.82:38
Harry Maguire challenges Steve Arnold unfairly and gives away a free kick. Steve Arnold takes the free kick.81:59
Neill Collins takes a shot. Save made by Steve Arnold. Inswinging corner taken left-footed by Barry Robson, clearance by Miguel Comminges.81:10
Tony McMahon takes a shot. Blocked by Mark Roberts. Corner taken by Barry Robson from the left by-line played to the near post, Miguel Comminges manages to make a clearance.80:41
Dave Kitson takes a shot. Save by Steve Arnold. Barry Robson takes a short corner.80:19
Anthony Grant takes a shot. George Long makes a save.78:57 Substitution
Substitution Greg Tansey is brought on as a substitute for Daniel Lopez.78:10
Corner taken left-footed by Barry Robson from the left by-line, save made by Steve Arnold.77:06
Free kick taken by Michael Doyle.77:06 Booking
Booking James Dunne is shown a yellow card.76:29
Free kick awarded for a foul by James Dunne on Kevin McDonald.76:00
Unfair challenge on Dave Kitson by Daniel Lopez results in a free kick. Indirect free kick taken by Michael Doyle.74:03
Indirect free kick taken by Steve Arnold.
Substitution Steve Beleck joins the action as a substitute, replacing Marcus Haber.74:03
The assistant referee flags for offside against Jonathan Forte.71:50
The ball is delivered by Callum McFadzean, save made by Steve Arnold.71:01
Barry Robson delivers the ball, Mark Roberts manages to make a clearance.70:40
Free kick awarded for a foul by Marcus Haber on Matthew Hill. Indirect free kick taken by Neill Collins.70:08
Free kick taken by Lee Hills.70:08 Booking
Booking Barry Robson shown a yellow card.69:46
Foul by Barry Robson on James Dunne, free kick awarded.68:14
The assist for the goal came from Daniel Lopez.68:14 Goal scored
Goal! - Lucas Akins - Stevenage 4 - 0 Sheff Utd Lucas Akins gets on the score sheet with a goal from the edge of the area to the bottom left corner of the goal. Stevenage 4-0 Sheff Utd.66:54
A cross is delivered by Matthew Hill.66:12
Matthew Hill crosses the ball, Lee Hills manages to make a clearance.65:07
Free kick awarded for an unfair challenge on Michael Doyle by Mark Roberts. Indirect free kick taken by Dave Kitson.63:53
Assist on the goal came from Anthony Grant.63:53 Goal scored
Goal! - Daniel Lopez - Stevenage 3 - 0 Sheff Utd Daniel Lopez scores a goal from the edge of the area to the top right corner of the goal. Stevenage 3-0 Sheff Utd.63:05
Callum McFadzean crosses the ball, save made by Steve Arnold.57:34
Lee Hills delivers the ball, Daniel Lopez has an effort at goal from close range which goes wide left of the target.56:25
The ball is swung over by Tony McMahon, clearance made by Mark Roberts. Matthew Hill produces a left-footed shot from just outside the penalty box that misses to the left of the target.55:57
Centre by Barry Robson, Mark Roberts makes a clearance.55:13
Foul by Barry Robson on James Dunne, free kick awarded. Free kick taken by Bondz N'Gala.53:28
Callum McFadzean takes a shot.52:26
Inswinging corner taken left-footed by Barry Robson, Harry Maguire takes a shot. Save made by Steve Arnold. Barry Robson takes a short corner.52:02
Shot by Daniel Lopez from outside the box goes over the net.51:05
Foul by Anthony Grant on Michael Doyle, free kick awarded. Free kick taken by Neill Collins.49:06
Assist on the goal came from Gavin Mahon.49:06 Goal scored
Goal! - Daniel Lopez - Stevenage 2 - 0 Sheff Utd Daniel Lopez fires in a goal from close in to the bottom right corner of the goal. Stevenage 2-0 Sheff Utd.48:57
The ball is swung over by James Dunne, clearance by Neill Collins.48:35
James Dunne decides to take the corner short.47:15
Anthony Grant produces a cross, clearance made by George Long.46:01
Outswinging corner taken left-footed by Barry Robson from the left by-line, Anthony Grant makes a clearance.45:01
The second half kicks off.45:01 Substitution
Substitution (Sheff Utd) makes a substitution, with Jonathan Forte coming on for Ryan Flynn.45:00 +1:35 Half time
Half Time The whistle is blown to end the first half.45:00 +1:00
Foul by James Dunne on Ryan Flynn, free kick awarded. Free kick taken by Neill Collins.45:00 +0:26
Foul by Lucas Akins on Callum McFadzean, free kick awarded. Indirect free kick taken by George Long.44:32
Shot by Lee Hills from deep inside the penalty area misses wide to the left of the target.43:56
A cross is delivered by James Dunne, Bondz N'Gala takes a shot. Matthew Hill gets a block in. Short corner taken by James Dunne from the right by-line.43:22
Daniel Lopez takes a shot. Save made by George Long. James Dunne takes a short corner.40:36
Assist on the goal came from Miguel Comminges.40:36 Goal scored
Goal! - Daniel Lopez - Stevenage 1 - 0 Sheff Utd Goal scored by Daniel Lopez from inside the penalty area to the bottom right corner of the goal. Stevenage 1-0 Sheff Utd.39:53
Anthony Grant has an effort at goal from just outside the box which goes wide of the right-hand upright.39:24
Centre by Lucas Akins, Marcus Haber takes a shot. George Long makes a save.35:40
Matthew Hill fouled by Anthony Grant, the ref awards a free kick. Matthew Hill takes the free kick.31:58
Free kick awarded for an unfair challenge on Tony McMahon by Anthony Grant. Indirect free kick taken by Harry Maguire.28:08
The referee blows for offside. Tony McMahon takes the indirect free kick.27:31
Tony McMahon sends in a cross, Barry Robson takes a shot. Steve Arnold makes a comfortable save.22:40
Ryan Flynn takes a shot. Steve Arnold makes a save. Corner taken by Barry Robson from the right by-line, Matthew Hill takes a shot. Steve Arnold makes a save.21:19
Tony McMahon gives away a free kick for an unfair challenge on Daniel Lopez. Free kick taken by Bondz N'Gala.20:14
Effort from just outside the area by Daniel Lopez goes over the target.18:37
The ball is crossed by Anthony Grant, Dave Kitson makes a clearance. Shot from just outside the box by Lucas Akins misses to the left of the target.17:48
Bondz N'Gala fouled by Ryan Flynn, the ref awards a free kick. Bondz N'Gala takes the free kick.16:13
Foul by Gavin Mahon on Barry Robson, free kick awarded. Indirect free kick taken by George Long.15:20
Lucas Akins takes a shot. Blocked by Matthew Hill. Outswinging corner taken right-footed by James Dunne played to the near post, clearance made by Kevin McDonald.13:47
James Dunne concedes a free kick for a foul on Tony McMahon. Tony McMahon takes the free kick.10:14
Foul by Ryan Flynn on James Dunne, free kick awarded. Free kick taken by James Dunne.9:29 Substitution
Substitution Callum McFadzean on for Jamie Murphy.9:06
Jamie Murphy is ruled offside. Free kick taken by Steve Arnold.6:56
Anthony Grant challenges Harry Maguire unfairly and gives away a free kick. Indirect free kick taken by Harry Maguire.5:45
Michael Doyle concedes a free kick for a foul on Anthony Grant. Lee Hills crosses the ball in from the free kick, clearance by Neill Collins.4:14
Free kick awarded for a foul by Dave Kitson on Gavin Mahon. Miguel Comminges takes the free kick.3:05
Daniel Lopez takes a shot. George Long gets a block in. Inswinging corner taken from the left by-line by James Dunne, Daniel Lopez concedes a free kick for a foul on George Long. George Long restarts play with the free kick.1:40
Free kick awarded for a foul by Michael Doyle on Anthony Grant. Free kick crossed right-footed by Miguel Comminges from right wing.0:00
The game gets underway.
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