Vassallo, 25, has been at Gorsey Lane since October, and will now stay with the Blues until 4th March.
The former Warrington Town player has featured 13 times for Rylands, scoring in a 4-0 victory over Radcliffe in December.
With Vassallo's short-term future secured, the club will now look to appoint a manager following the recent departure of Jody Banim.
Photo credit: Warrington Rylands
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