Parramatta will give Jarryd Hayne until the 11th-hour to prove his fitness for the battle of the west with Penrith at Parramatta Stadium on Friday.
Hayne, who has been sidelined with a knee injury sustained initially against the Panthers in a trial game, returned against the Warriors in round two but lasted just 16 minutes before being forced off the field.
He missed last Saturday's 42-6 hammering by North Queensland and although the Eels' medical team are wary of rushing him back, Hayne ran with the team on Thursday morning.
However, rookie winger Ken Sio lined up at fullback for the start of an open play session in the team's final run before facing Ivan Cleary's side, with Hayne putting up bombs for the youngster to catch.
Veteran winger Luke Burt was sacrificed for Hayne in round two and the 31-year admits he's unsure if he'll be the man to miss out again should the 2009 Dally M Medallist return to action.
