CRAWLEY boss John Yems revealed Caleb Watts would be out for up to three months due to a hamstring injury.
The Saints youngster joined the League Two outfit on loan last week.
He was named on the bench for their long trip to Carlisle United and was introduced with the Red Devils 1-0 up, through an Ashley Nadesan goal.
Watts came on just past the hour mark, but was withdrawn again on 81 minutes due to his hamstring problem.
Carlisle battled back to draw 1-1, with substitute Lewis Alessandra striking a dramatic late equaliser.
And giving an update on the Australia youth international on Thursday, Yems confirmed Watts would be heading back to his parent club for further assessment.
The Crawley boss said: "Caleb is out for three months.
"He played 17 minutes bless him and I spoke to him this morning and he may have to have surgery.
“Southampton have been decent with it and they are dealing with it at the moment and I will sort it out with them when I get out of this press conference."
Watts made four senior appearances for Saints last season, including his debut in the FA Cup against Shrewsbury Town.
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