Cheltenham avoided an FA Cup shock as they gained a hard-fought win at Luton.
Darryl Duffy put the Robins ahead when he raced on to Scott Brown's goal-kick but Aaron O'Connor equalised when he converted from Robbie Willmott's cross.
Marlon Pack's solo effort made it 2-1 and O'Connor levelled with a powerful finish before Luke Summerfield's first-time shot restored the visitors' lead.
Duffy was sent off for foul language but Cheltenham scored again as Russell Penn finished off a counter-attack.
VIEWS FROM THE DRESSING ROOM
Luton manager Gary Brabin told BBC Three Counties Radio:
"I am disappointed. We could have won today. You dream of getting in the hat for the next round, and with the big boys coming in it's a bit harder to take.
"Cheltenham are on a roll at the moment and when you have got that belief, things fall for you. They only had five or six chances on our goal and put away four of them.
"I thought we played some really good football. We played on the front foot which is what I want us to do. We always looked like we were going to score goals today, but it's disappointing the goals we have conceded."
Cheltenham Town manager Mark Yates told BBC Gloucestershire:
"It was a great game. We weren't as good as we have been and I think that's credit to them.
"We know we've been in a real game against a really decent side. On chances I think we deserved to get through but they gave us one hell of a scare.
"Scoring the early goal made us a bit lax and not as sharp as we could have been. They (the players) really wanted to win today and I'm just delighted to be in the next round."
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Live Text Commentary
Full Time The final whistle goes and the game is over.90:00 +4:08 Substitution
Substitution Jeff Goulding on for James Spencer.90:00 +2:52
Brian Smikle provided the assist for the goal.90:00 +2:52 Goal scored
Goal! - Russell Penn - Luton 2 - 4 Cheltenham Russell Penn scores a goal from inside the penalty area to the top right corner of the goal. Luton 2-4 Cheltenham.90:00 +2:12
Joshua Low takes a shot. Save by Kevin Pilkington.90:00 +1:30
The ball is swung over by Adam Watkins.89:52
Unfair challenge on Aaron O'Connor by Joshua Low results in a free kick. Alex Lawless restarts play with the free kick.87:35
Alex Lawless produces a right-footed shot from a long way out and strikes the post.84:04
Indirect free kick taken by Scott P Brown.84:04 Substitution
Substitution Kaid Mohamed goes off and Brian Smikle comes on.84:04
The offside flag is raised against Janos Kovacs.82:26
Robbie Willmott takes the free kick.82:26 Dismissal
Dismissal Darryl Duffy receives a red card for second bookable offence.82:08
Free kick awarded for an unfair challenge on Aaron O'Connor by Darryl Duffy.80:49
Aaron O'Connor takes the indirect free kick.80:49 Booking
Booking Booking for Darryl Duffy for unsporting behaviour.80:39
Free kick awarded for an unfair challenge on John Kissock by Alan Bennett.79:05
The ball is swung over by James Spencer.78:26
Free kick awarded for an unfair challenge on Alan Bennett by Danny Crow. Scott P Brown restarts play with the free kick.77:52
Outswinging corner taken right-footed by Marlon Pack from the right by-line, Header on goal by Alan Bennett from inside the box goes harmlessly over the target.
Shot from long range by Marlon Pack misses to the right of the target.75:04 Substitution
Substitution John Kissock on for Keith Keane.75:04 Booking
Booking Luke Summerfield is given a yellow card.72:49
Danny Crow delivers the ball, Scott P Brown makes a save.72:10
Outswinging corner taken right-footed by Marlon Pack from the right by-line, Effort on goal by Luke Summerfield from inside the area goes harmlessly over the bar.70:24
Inswinging corner taken from the left by-line by Robbie Willmott.69:03
Danny Crow fouled by Marlon Pack, the ref awards a free kick. Indirect free kick taken by Robbie Willmott.67:04
The ball is delivered by Daniel Gleeson.65:13
Keith Keane fouled by Marlon Pack, the ref awards a free kick. Jake Howells restarts play with the free kick.63:02
Assist by Darryl Duffy.63:02 Goal scored
Goal! - Luke Summerfield - Luton 2 - 3 Cheltenham Luke Summerfield scores a goal from just outside the penalty box to the bottom right corner of the goal. Luton 2-3 Cheltenham.62:06
Daniel Gleeson fouled by Sido Jombati, the ref awards a free kick. Keith Keane takes the free kick.60:49
Daniel Gleeson challenges Darryl Duffy unfairly and gives away a free kick. Indirect free kick taken by Marlon Pack.61:21 Booking
Booking Daniel Gleeson goes into the referee's book for unsporting behaviour.60:24
Outswinging corner taken right-footed by Robbie Willmott played to the near post, clearance made by Luke Summerfield.57:45
Robbie Willmott concedes a free kick for a foul on Sido Jombati. Free kick crossed right-footed by Marlon Pack.56:26
Darryl Duffy is adjudged to have handled the ball. Keith Keane takes the free kick.54:24
Robbie Willmott sends in a cross.53:27
Danny Crow crosses the ball.50:44
Danny Crow provided the assist for the goal.50:44 Goal scored
Goal! - Aaron O'Connor - Luton 2 - 2 Cheltenham Aaron O'Connor scores a goal from just outside the penalty box to the bottom right corner of the goal. Luton 2-2 Cheltenham.50:08
Darryl Duffy gives away a free kick for an unfair challenge on Keith Keane. George Pilkington takes the free kick.48:29
Keith Keane concedes a free kick for a foul on James Spencer. Kaid Mohamed produces a strike on goal direct from the free kick.45:37
The ball is swung over by Daniel Gleeson.45:01
The referee gets the second half underway.45:00 +2:59 Half time
Half Time The ref blows to signal half-time.45:00 +2:38
Marlon Pack takes the outswinging corner, Keith Lowe takes a shot.44:47
The assist for the goal came from Joshua Low.44:47 Goal scored
Goal! - Marlon Pack - Luton 1 - 2 Cheltenham Marlon Pack finds the back of the net with a goal from inside the box to the bottom left corner of the goal. Luton 1-2 Cheltenham.43:25
A cross is delivered by Joshua Low, clearance by George Pilkington.42:19
Daniel Gleeson fouled by Alan Bennett, the ref awards a free kick. Kevin Pilkington restarts play with the free kick.42:15
Inswinging corner taken from the left by-line by Marlon Pack.39:25
Assist on the goal came from Robbie Willmott.39:25 Goal scored
Goal! - Aaron O'Connor - Luton 1 - 1 Cheltenham Aaron O'Connor finds the net with a goal from close range to the bottom right corner of the goal. Luton 1-1 Cheltenham.38:21
Adam Watkins takes a shot. Scott P Brown makes a save.37:17
Free kick awarded for an unfair challenge on James Spencer by Jake Howells. Marlon Pack crosses the ball from the free kick right-footed from right wing.36:36
Sido Jombati crosses the ball, Jake Howells makes a clearance.35:42
Alan Bennett fouled by Robbie Willmott, the ref awards a free kick. Scott P Brown takes the indirect free kick.34:21
Keith Keane concedes a free kick for a foul on James Spencer. Marlon Pack takes the indirect free kick.33:19
Outswinging corner taken by Robbie Willmott from the right by-line, Header from deep inside the area by Janos Kovacs goes harmlessly over the crossbar.33:04
Adam Watkins takes a shot. Save made by Scott P Brown.32:01
Joshua Low gives away a free kick for an unfair challenge on Danny Crow. Free kick taken by Keith Keane.27:59
Alan Bennett crosses the ball, clearance made by Danny Crow.25:06
Free kick awarded for a foul by Aaron O'Connor on Joshua Low. Scott P Brown takes the free kick.24:11
Russell Penn gives away a free kick for an unfair challenge on Adam Watkins. Jake Howells takes the indirect free kick.23:09
The ball is delivered by Aaron O'Connor.22:27
Jake Howells delivers the ball, Joshua Low makes a clearance.20:22
Aaron O'Connor gives away a free kick for an unfair challenge on James Spencer. Marlon Pack restarts play with the free kick.16:34
Corner taken right-footed by Keith Keane from the right by-line, clearance made by Marlon Pack.15:29
Daniel Gleeson fouled by Marlon Pack, the ref awards a free kick. Robbie Willmott restarts play with the free kick.15:25
Adam Watkins sends in a cross.14:49
Russell Penn takes a shot. Save by Kevin Pilkington.13:41
The ball is crossed by Adam Watkins, Janos Kovacs has a headed effort at goal from close range which goes wide of the left-hand upright.13:21
Inswinging corner taken from the right by-line by Adam Watkins.12:23
Aaron O'Connor sends in a cross, Danny Crow has a headed effort at goal from deep inside the area missing to the left of the target.11:54
The ball is sent over by Joshua Low, clearance made by Janos Kovacs.8:50
Robbie Willmott crosses the ball.8:18
Unfair challenge on Robbie Willmott by Sido Jombati results in a free kick. Jake Howells takes the free kick.5:49
Robbie Willmott concedes a free kick for a foul on Sido Jombati. Marlon Pack restarts play with the free kick.5:16
Shot from outside the penalty box by Russell Penn goes wide right of the goal.1:44
Assist by Scott P Brown.1:44 Goal scored
Goal! - Darryl Duffy - Luton 0 - 1 Cheltenham Darryl Duffy grabs a goal from close in to the bottom right corner of the goal. Luton 0-1 Cheltenham.1:04
Robbie Willmott takes a shot. Sido Jombati gets a block in.0:32
Marlon Pack takes a shot. Daniel Gleeson makes a clearance.0:00
The referee starts the match.
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