The 19-year-old arrived on a month's loan from the National League North club after utility-man Melboune opted to end his third spell at Keys Park this week.
Gatter, pictured, kicked off his career at Burton Albion before linking up with Boston United. Signed by Trinity in the summer, he is equally as comfortable playing as a defender or midfielder and spent October on loan in the EVO-STIK League Premier Division with Coalville Town.
The Pitmen paid tribute to Melboune in a short statement on Friday as they prepared to host Cleethorpes Town in the second qualifying round of the Buildbase FA Trophy on Saturday.
The club said: "Everyone associated with the football club would like to thank Alex for his no nonsense efforts and wish him all the best for the future."
Image courtesy of Pitchero
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