Having played for us in a midweek behind closed doors Friendly, Fionn joins up with Spencer Day’s team ahead Saturday’s long trip to Devon.
Mooney came through the ranks at Crystal Palace, where he was a constant fixture in U18 Premier League and Premier League 2 games, as well as making appearances in the EFL Trophy and FA Youth Cup.
He left Palace in August 2023 for a move to Real Valladolid in Spain, before returning to England.
The talented young midfielder briefly joined Enfield Town just last month, but now moves to Hampshire to bolster the Yellows squad.
Mooney has been allocated shirt number 33.
View the updated Squad list.
