With just over a month to go until the end of the season, several players are also nearing the end of their contracts.
While the race to win promotion from League One remains incredibly close, clubs will be weighing up who they could offer new deals at the end of the campaign.
Negotiations have already begun with some players over new deals, though some deals have been put on hold until the summer.
We’ve taken a look at some of the players whose contracts are set to expire this summer, putting them into a starting XI.
There will certainly be interest from elsewhere:
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1. GK: Viktor Johansson (Rotherham)
After starting the season as Rotherham's first-choice goalkeeper, the 23-year-old has lost his starting place to Josh Vickers. Johansson is one of several Millers players who will be out of contract this summer.
Photo: George Wood
2. RB: Jack Hunt (Sheffield Wednesday)
After returning to Sheffield Wednesday on a one-year deal in the summer, Hunt, 31, has been a regular starter at Hillsborough, making 33 League One appearances this season.
Photo: Jacques Feeney
3. CB: Bailey Wright (Sunderland)
There was speculation about Wright's future last summer, yet the Australian international stayed at the Stadium of Light and has become a key player at heart of Sunderland's defence again.
Photo: JPI Media
4. CB: Michael Ihiekwe (Rotherham)
Rotherham have the best defensive record in League One, and 29-year-old Ihiekwe has been a key member of the team's backline. The centre-back has put negotiations about a new deal on hold until the close of the campaign.
Photo: Nathan Stirk