Onuoha sustained his injury after a clash of heads with team-mate Steven Caulker against the Gunners, while fellow defenders Isla and Furlong are nursing knee and calf problems respectively.
The injuries could leave Chris Ramsey’s side light at the back for the visit of Spurs, but Brazilian midfielder Sandro is available to face his former club having recovered from a knee injury.
“Hopefully Sandro will be able to last longer than an hour tomorrow – it’s part of his conditioning process,” Ramsey said.
“He had to come off because we didn’t want to risk him getting injured again. He is growing in stature.”
Provisional squad: Green, McCarthy, Caulker, Furlong, Yun, Ferdinand, Onuoha, Isla, Hill, Traore, Kranjcar, Henry, Sandro, Phillips, Hoilett, Wright-Phillips, Vargas, Austin, Zamora, Zarate.
Boy that looks bad...
Ned, Isla, Furlong all injury doubts
Looking B.A.D with a capital B