
The Blues went down 2-1 in Norfolk on Saturday afternoon as they missed a chance of moving off the bottom of the table.
Goalkeeper Jack Beresford was sent off in the first half before Ewan Parlett put Leiston ahead early on in the second period.
But Gorleston Reserves scored two quick goals and held on to take the points at the Nest.
Leiston host FC Peterborough in their next game next weekend, Saturday 14th March.