Reds had a day to forget as they suffered their first away defeat of the League 2 campaign on a chastening afternoon at the One Call Stadium.
Two goals either side of half-time by Nathan Thomas and Mitch Rose put the Stags in charge and it got worse for Reds when Gwion Edwards was shown a straight red card for his challenge on Nicky Hunt.
Mansfield made the most of their man advantage. Matt Green and Craig Westcarr added further goals while at the other end Brian Jensen had a quiet afternoon against his former club while Reds also lost striker Matt Harrold to a hamstring injury in the first half.
Manager Mark Yates made one change to the side that shared a goalless draw with Wycombe in our last game a fortnight ago with Liam Donnelly returning after suspension to replace Joe McNerney, who was sidelined by a knee injury.
The Stags, who had drawn their three previous home games, were on the front foot from the kick off and Freddie Woodman came out of his goal on two minutes to block a shot from Westcarr, who had been found by Hunt’s pass.
Woodman was then happy to see Adam Chapman’s volley from 25 yards fly past his right-hand post but Reds gradually worked their way into the game, although the contest lacked fluency in the first 30 minutes because of a succession of free kicks.
Jensen made a comfortable save from Donnelly’s back-post header before the visitors had to make a change midway through the half when Matt Harrold suffered a hamstring injury when he stretched trying to tee up Roarie Deacon with a pass that appeared to strike the hand of defender Ryan Tafazolli.
His replacement Lee Barnard tested Jensen with a snap shot which the keeper held to his right before Edwards stretched his legs for the first time, racing past Hunt to find Jimmy Smith in the box. The midfielder dummied the ball but Deacon’s shot was blocked.
The deadlock was broken a minute before the break. Barnard’s pass 25 yards out to Smith was intercepted by Thomas, who burst into the box before giving Woodman no chance with rising drive from 12 yards.
On the balance of play it was just about deserved and within two minutes of the re-start they had doubled their lead. Simon Walton’s headed clearance at a corner fell to Rose 20 yards out and his low volley took a deflection, wrong-footing Woodman on its way into the net.
It got worse for Crawley a few minutes later when Edwards got a straight red for a bad challenge on Hunt in front of the dugouts.
Reds made their second change on 55 minutes with Luke Rooney replacing Lewis Young and Rooney fired wide from distance before Walton’s ambitious attempt to beat Jensen from a free kick from the halfway line floated wide of the post.
The post denied the Stags a third midway through the half when Matt Green for once got the better of Sonny Bradley but his right-foot shot from 15 yards cannoned back off the right-hand upright.
But the home side then scored twice in two minutes as Reds were cut apart at the back. On 70 minutes Chapman’s cross-field pass found Westcarr in space on the left and he teed up Green for a tap-in from three yards.
It got worse moments later when Westcarr waltzed through a gaping hole in the centre of Reds’ defence and side-footed past a totally exposed Woodman to make it 4-0.
It was now a case of damage limitation for Reds who could have conceded further goals. Christian Scales did enough to put off Green when he looked certain to convert a close-range header then Woodman flung himself to his right to deny Thomas a second from a shot on the turn.
Reds rallied late on but efforts from Rooney and substitute Bobson Bawling failed to test Jensen and the visitors were left to lick their wounds and regroup ahead of next Saturday’s home game against Yeovil Town.