Three players have agreed to stay on loan at Bristol Rovers until the end of the season.
Chesterfield defender Aaron Downes, 26, Crystal Palace midfielder Andy Dorman, 29, and Leicester defender Cian Bolger, 19, have all signed new deals.
Meanwhile, Brighton goalkeeper Michael Poke, 26, has extended his spell at the Memorial Stadium by a further month.
Chairman Nick Higgs told the club website: "All four player have helped give us some much needed stability."
All four arrived at the club during Paul Buckle's reign as manager - Bolger was signed in the summer, Dorman was drafted in in November, while Poke and Downes arrived just two days before Buckle's departure.