Izale McLeod scored his second goal in two games to knock Championship side Ipswich Town out of the Capital One Cup.
He scored a scrappy goal 20 minutes into extra-time as Reds caused yet another cup upset.
After a goalless 90 minutes of high speed play, it took until the 110th minute before the deadlock was finally broken from short-range by McLeod following unpretty build-up work by Gwion Edwards and Sonny Bradley.
Reds made two changes to the side which beat Barnsley 1-0 on Saturday with the injured Josh Simpson rested and Ryan Dickson dropped to the bench.
Sonny Bradley made his competitive debut at left back and Bobson Bawling made his first competitive start having come on at Barnsley, playing on the right wing.
Ipswich made eight changes to the side which won 2-1 against Fulham.
Crawley played Louis Young up front behind Izale McLeod as nine players made their home debuts in a competitive match, ten if you include Gwion Edwards beginning his second spell at the Checkatrade.com Stadium.
Reds made a strong start by carving out three good chances in the first 15 minutes.
Dean Leacock nodded a corner kick by Conor Henderson against the post.
Jimmy Smith then put a good ball through for McLeod to have a go but he couldn’t connect, then Lanre Oyebanjo blazed a shot over the bar.
McLeod nearly gave Crawley the lead when he turned and fired in front of goal only to see the ball inches wide.
But Ipswich should have definitely taken the lead in the 21st minute when Alex Henshall put Frank Nouble through only for him to side foot his shot off-target from right yards.
The Tractor Boys stepped up after the break and had long periods in possession during which they put Crawley under pressure.
Nouble forced Jensen to make a save early on before Paul Taylor blasted off-target.
Eliiott Hewitt put in a cross which none of his team-mates pushing forward could connect with as Reds breathed a sigh of relief.
Alex Henshall was quite a handful for the visitors along their left flank but it was Taylor who was denied spectacularly by Jensen.
John Gregory made two substitutions and handed two more home debuts, replacing Young up front with new signing Charles Banya while Bawling came off and Dickson went on.
Dickson went on the left wing, switching flanks with Gwion Edwards.
For Ipswich, substitute Balint Bajner came close to settling the game in normal time with a thundering smash against the crossbar from 25 yards.
McLeod volleyed over the bar following a defensive error then in the final minute was put through only to be prevented from getting the winner from short-range by keeper Bartosz Bialkowski.
The game finished normal time at 0-0 which remained the score after an uneventful first half of extra-time.
Finally in the 110th minute McLeod bundled in the winner from four yards after a bouncing to him from Jimmy Smith as Reds clinched a brilliant cup scalping.
REDS: Jenson, Oyebanjo, Henderson (O’Connor 92), Leacock, Bradley, Edwards, Smith, McLeod, Walsh, Young (Banya 55) Bawling (Dickson 60).
Unused subs: Essam, Rose, Richefond, Isaacs
IPSWICH: Bialkowski, Chambers, Berra, Bru (Bishop 76), Hewitt, Wordsworth, Henshall, Taylor (McQueen 79), Clarke, Marriott (Bajner 62), Nouble
Unused subs: Gerken, Hyam, Lawrence, Wyatt
REFEREE: Andy Haines
ATTENDANCE: 3,043 (822 away)
MAN OF THE MATCH: Jimmy Smith