David Moyes's side need just one point against Southampton this afternoon in order to qualify for the Europa League, but was initially unsure if they would have their first-choice goalkeeper available.
"I don't know," Moyes said when asked if Fabianski would make it earlier this week.
"We don't think it is quite as bad as we thought but whether he is available it will be a last-minute call."
Fabianski does start though, with Jarrod Bowen also replacing Said Benrahma further forward.
West Ham vs Southampton teams
West Ham: Fabianski, Coufal, Dawson, Ogbonna, Cresswell, Soucek, Rice, Bowen, Lingard, Fornals, Antonio
Subs: Balbuena, Yarmolenko, Benrahma, Noble, Diop, Fredericks, Johnson, Randolph, Odubeko
Southampton: McCarthy, Walker-Peters, Bednarek, Vestergaard, Salisu, Diallo, Armstrong, Minamino, Ward-Prowse, Redmond, Ings
Subs: Stephens, Romeu, Djenepo, Obafemi, Tella, Walcott, N’Lundulu, Forster, Ferry