Brad Arthur concedes the indefinite loss of Blake Ferguson stings but says it's a perfect chance for other Eels to lift at a crucial time.

Heading into Saturday's match against the Warriors, the Parramatta coach also insisted he "hasn't heard anything" about star winger Semi Radradra wanting to return to the club from French rugby.

Ferguson has been hospitalised for the past week after suffering an allergic reaction to antibiotics he took to treat the knee infection which sidelined him last round. No date is set for his comeback.

"Hopefully he might get out [of hospital] over the weekend and then we'll just see where he gets to from there," Arthur said.

"But we're certainly not going to look at rushing him back ... His health is the priority."

Rookie Ethan Parry will play his second match covering for the NSW Origin winger against the Warriors at Bankwest Stadium, with mid-year recruit Waqa Blake to debut for Parramatta in the centres.

While Ferguson averages 165.7 metres per game and is almost akin to an extra forward in yardage sets, Arthur can see some positives in his absence.

"It provides an opportunity to someone else. That was Ethan Parry last week who did a really good job, he got to make his debut," Arthur said.

"With Fergo, it's unfortunate and it's not what we want but I certainly don't want to see him banged up in hospital either, so that's probably more to the point.

"Whenever you lose a quality player it's going to hurt but it's an opportunity for Ethan and it's an opportunity for everyone else to stand up."

Arthur said he only learned of Radradra being linked to Parramatta at training on Friday.

"One of the boys said it this morning. First I've heard of it. I haven't heard anything about it ... Unless he's spoken to someone else at the club, but I'm sure I'd know about it," Arthur said.

Though he is open to coaching the rampaging Radradra again, Arthur is pleased with the progress of fellow Fijian winger Maika Sivo, who leads the NRL with 13 tries in his first season.

"We've got our own Semi Radradra anyway, haven't we?" Arthur said of Sivo.

"If Semi wanted to come back to the club of course we'd be interested, but I haven't heard anything about it."

After a disappointing tackling display in the 36-24 defeat to Manly on Sunday, Arthur has demanded more starch in defence from his players to contain the Warriors.

Parramatta are sixth after winning three from their past four but Arthur acknowledged every fixture leading into the finals is critical with a slew of sides pushing for the eight.

"It's really important but every game for us at the moment has been important. The priority ... is the response to last week," he said.

"We didn't start well and we probably got to a false lead and then just before half-time we were very, very poor.

"We've got to get better when those periods go against us [so] that we can try to stop them or stop a bit of momentum.

"It was defence last week. It had nothing to do with our ball handling because we didn't touch the ball for 10 sets [when Manly were scoring]."

Arthur commended the 10th-placed Warriors for their grittiness in recent rounds, with the New Zealand club coming off a draw and two victories.

"They've had some close games where they've hung in and hung in and [ground] away," he said.

"We're expecting no different. They're obviously playing with a bit of confidence as well."