Josh Simpson marked his return to the side following the birth of his new son with a goal but Crawley were pegged back as Shrewsbury earned a point.
The Reds skipper put the visitors ahead with his second goal of the season midway through the first half, before the League One strugglers levelled through Paul Parry in the second half and the hosts twice struck the woodwork.
Manager John Gregory again shuffled his pack with four changes. In came Rory Fallon for his full debut, along with Simpson, Mark Connolly and Gary Dicker. Jamie Proctor, Matt Tubbs and Paul Connolly dropped to the bench while Andy Drury was injured.
Shrews began the match looking like a side lacking in confidence and Reds deservedly took the lead on 24 minutes, Simpson reacting quickest when Billy Clarke struck the wall with a free kick, to fire into the bottom corner for a 1-0 lead.
Shrews, looking for a first home win since November, came close to levelling before the break when Miles Storey latched onto Kyle McFadzean’s poor backpass and slammed his shot against the inside of the post.
At the start of the second half Mike Jones tested home goalkeeper Joe Anyon from outside the area before Shrewsbury were level on 55 minutes.
A cross from the right was only half cleared and Paul Parry let fly with a volley into the far corner as Paul Jones just failed to keep it out.
Shrewsbury saw a penalty shout turned down when Joe Mills went down under Mark Connolly’s challenge, while at the other end substitute Jamie Proctor headed Sadler’s cross just over.
Shrewsbury rattled Crawley’s goal for a second time when Parry’s drive from 25 yards crashed back off the post, and in the 89th minute there were more than a few nerves when a scramble was only just cleared by Joe Walsh.
It a final push in injury time, Proctor was only denied by a fine save from Anyon, while Billy Clarke’s snap-shot was turned away as it finished honours even.