Centre-back Josh Yorwerth has agreed a one-year deal to join Crawley following a successful loan period with the League Two club last season.
Yorwerth, 21, was released by Ipswich in May and made 24 appearances for Crawley after joining in September.
The Wales under-21 international has the option to extend his contract at the Red Devils by another year.
"Josh is a player we definitely feel is capable of improving a lot," head coach Dermot Drummy said.
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