Wigan manager Roberto Martinez believes the club could have to sign up to 14 players this summer if they are to make an immediate return to the Premier League.
The Latics might have to play as many as 60 games next season, with 46 matches in the Championship, a minimum of six in the Europa League, as well as FA Cup and Capital One Cup ties, and a potential appearance in the play-offs.
Martinez has already revealed that the club will lose the out-of-contract quartet of Antolin Alcaraz, Franco Di Santo, Maynor Figueroa and Ronnie Stam, while three more of his current squad - Joel Robles, Paul Scharner and Angelo Henriquez - are only on loan.
In addition, Wigan are expected to receive offers from top-flight clubs for players such as Shaun Maloney, James McCarthy, Callum McManaman and Arouna Kone.
Taking all of that into consideration, the former Swansea manager is adamant that the FA Cup winners will need to be busy in the transfer market over the summer.
"Next season there will be six guaranteed European games, the cups and 46 league games. There will be weeks when we play Thursday, Saturday and Tuesday,” Martinez said.
“This season we had a squad of 22 players, 24 with the youngsters: we will need 27. You can imagine we need between 12 and 14 players to come in besides what we are doing with the loan players.”