Leeds' hopes of becoming the first team to successfully defend rugby league's world club title have received a significant blow with incumbent NSW captain Danny Buderus not expected to be fit for Sunday's clash with Manly.

Sea Eagles coach Des Hasler, speaking after Sunday's 34-26 warm-up win over Harlequins in London, suggested Super League champions Leeds were foxing over their injury long list and that hooker Buderus had been "rested" from last Friday's brutal game against Hull KR.

But Buderus, 31, visited a doctor for knee scans late on Monday and the club believes he'll be unable to play in Sunday's World Club Challenge clash with NRL champions Manly at Elland Road.

"We won't get the scans back for a day but to be perfectly honest, it doesn't look good for Danny," Leeds chief executive Gary Hetherington told AAP.

"Initial indications are that he has a problem with his cartilage in his knee, that it is a cartilage problem. Generally, that is a four-week injury.

"We have a number of injuries and that is just being honest. Rob Burrow (back) is looking very doubtful as well."

Other Leeds casualties include second rower Ali Lauitiiti (hamstring), second rower Carl Ablett (niggling injuries) prop Ryan Bailey and utility back Lee Smith (both concussion).

Hasler said after the Eagles' first game since the 2008 grand final: They tell us they've got eight injured, eight won't play. We've been down that road before so well see.

"We'll assess that when we get up there but I think they'll have a full complement.

"I notice Danny Buderus didn't play (on Friday), the young halfback Rob Burrow didn't play, so I would imagine they were resting them."

Hetherington denied any gamesmanship while Leeds five-eighth Danny McGuire told the Press Association: "We're struggling at the minute.

"It's hard to know what to put it down to because our conditioners and physios are probably the best in the game and really look after our bodies and make sure we are doing the right things.

"It would have been nice to get all our players out there but, if we lose or don't perform, we won't be using it as an excuse." The Rhinos trained twice on Monday before Buderus visited a specialist.

Manly recovered from their comeback win over Quins with a swim at their Richmond base before a five-hour bus journey to their new camp at the Leeds Marriott. Hasler gave his men the afternoon off.

Despite a few missing stars on both sides - Manly's Brent Kite and Tony Williams did not make the trip to the UK - Rugby Football League officials are confident of another 30,000-plus crowd at Elland Road on Sunday evening.

Brought to you by AAP © 2024 AAP