Coventry City have to win their four remaining games and hope that either Gillingham, Shrewsbury or Bury fail to pick up a point in their games if they are to stay in League One.
City's 1-0 win over Peterborough, saw City move to 35 points, two behind Chesterfield who beat fourth from bottom Port Vale 1-0 and eight behind Swindon Town who drew 1-1 with MK Dons at home.
Fifth from bottom Gillingham drew 1-1 with sixth placed Millwall to go onto 46 points, the same as Shrewsbury who beat Rochdale 1-0 and Bury who lost 2-0 at home to fourth placed Bradford City.
Sheffield United were promoted to the Championship thanks to a 2-1 win at Northampton whilst second placed Bolton lost 1-0 at fifth placed Scunthorpe United.
Fleetwood stay third after losing 2-0 at Oldham.
Southend are down to seventh after losing 2-1 at Charlton, who travel to the Ricoh Arena on Friday afternoon.
Bristol Rovers are eighth after a 1-0 win at AFC Wimbledon and Oxford stay tenth after a 1-1 draw at Walsall.
Doncaster Rovers will play in League One next season after beating Mansfield Town 1-0 at home.