The Eels have refused to blame the absence of star fullback Jarryd Hayne for a poor outing at Penrith on Friday night.

Hayne not to blame: Mannah

Parramatta captain Tim Mannah refused to blame last night's smackdown by the hands of Penrith on the absence of superstar fullback Jarryd Hayne, saying the team let themselves down with their own ill-discipline. 

The Eels completed just 56 per cent of their sets in a first half shut-out during a 38-12 defeat at the hands of their local rivals. But Mannah said it wasn't because their co-captain wasn't there. 

"I don't think that was the issue tonight. It was just a matter of us making some simple errors and then letting them march down the field way too easy," Mannah said after the game. 

"Tonight, we probably didn't have everyone doing their job the best they could. We're the kind of team that needs everyone across the park turning up and doing the job the best they can. We let ourselves down tonight with the simple things, not aiming up in defence." 

Coach Brad Arthur said his team was guilty of overplaying their hand without their second-leading tryscorer. 

"[The loss has] got nothing to do with Jarryd for me. Maybe we tried too hard in the first half to create things that weren't there," he said. 

"But when you're completing at 56 per cent, it's very hard to come up with repeated sets in defence and that was the difference."

While he admitted that Hayne could've played if it were a must-win game, Arthur said he wasn't prepared risking injury to arguably the most significant cog in the team. 

"It'd be different if we were playing a semi-final, but I have to go on the advice. I've got good staff around me and they said it was too big a risk factor. We'd much rather him missing tonight than six to eight weeks," he said. 

"The way he carries the footy and the explosive movements that he makes, he was at a big risk of doing a hamstring or something like that.

"Obviously at the end of the day he wants to come back and play for his club but he knew deep down as well that he wasn't 100 per cent and his body hadn't recovered well enough to compete and play at a good enough standard without risking any injury."

The Eels will welcome the return of their fullback for next Friday's match against the Cowboys, particularly after replacement fullback Justin Hunt was hooked from the role by Arthur after just 30 minutes. 

In his first outing in Eels colours, Hunt was shifted to the wing and replaced by Ken Sio. 

"Justin came up with a couple of errors there, but it was more about protecting him and getting his confidence back up and putting him on the wing. Kenny's played there before and he's done a reasonable job for us before," he said.