Cayless injured his hamstring ten minutes into Friday night’s 22-12 Preliminary Final win over the Bulldogs and is racing to be passed fit for the decider.
Coach Daniel Anderson has named the same side from the win over the Bulldogs, which includes Nathan Hindmarsh, who will become the second most capped Eel of all time when he takes the field on Sunday.
Hindmarsh, currently on 259 career games, will move past fellow Eels great Ray Price when he runs out for the 260th time.
Only Brett Kenny, on 265 career appearances for Parramatta, remains ahead of Hindmarsh on the all time list.
The team to play the Storm also includes fullback Jarryd Hayne and hooker Matt Keating, both of whom will take the field after accepting early guilty pleas on grade one charges stemming from the win over the Bulldogs.
Squad: Jarryd Hayne, Luke Burt, Krisnan Inu, Joel Reddy, Eric Grothe, Daniel Mortimer, Jeff Robson, Nathan Cayless, Matthew Keating, Fuifui Moimoi, Nathan Hindmarsh, Ben Smith, Todd Lowrie. Subs: Kevin Kingston, Feleti Mateo, Joe Galuvao, Tim Mannah.