Saints boss Ralph Hasenhuttl said Ings would be assessed on a hamstring problem sustained at Tottenham on April 21, having initially feared the striker may miss the remainder of the season.
On-loan Takumi Minamino is available to return to the squad after being ineligible against his parent club Liverpool on Saturday but Ryan Bertrand (calf), Oriol Romeu (ankle) and Will Smallbone (knee) remain out.
Crystal Palace have no new injury worries, but could make changes to their starting XI given the quick turnaround following Saturday's 2-0 win at already-relegated Sheffield United.
Nathan Ferguson has returned to first-team training, but he is not expected to be rushed back during the final two weeks of the campaign after struggling with a knee injury and more recently a thigh issue during the last 18 months.
Southampton provisional squad: Forster, McCarthy, Walker-Peters, Vestergaard, Stephens, Bednarek, Salisu, Ward-Prowse, Diallo, Ramsay, Jankewitz, Redmond, Armstrong, Minamino, Tella, Walcott, Djenepo, Adams, Ings, Obafemi, N'Lundulu, Ferry.
Crystal Palace provisional squad: Guaita, Ward, Cahill, Kouyate, Van Aanholt, Riedewald, Milivojevic, Ayew, Eze, Zaha, Benteke, Butland, Clyne, Dann, Kelly, Tomkins, Mitchell, Schlupp, McCarthy, Mateta, Batshuayi, Hannam, Hennessey, Rak-Sakyi.