Winger Tom Briscoe and second-row Carl Ablett are the internationals who were crocked in their heavy defeat at Widnes.
McDermott confirmed yesterday they could be out for two months along with youngster Ashton Golding adding to their mounting casualty list that sees former Great Britain forward Jamie Jones-Buchanan and talented Stevie Ward sidelined, too.
However, it was when captain and scrum-half Danny McGuire ruptured his knee ligaments the week before against Huddersfield, that the Leeds chief will probably have been instilling into his side the belief that resilience, doggedness and sheer will will be more important than ever before.
Leeds, of course, must find some creativeness to break down a North Queensland Cowboys side tomorrow evening that, in comparison, represents the same 17 that defeated Brisbane Broncos in their NRL Grand Final last October.
But on a cold, dank night at Headingley, McDermott knows, without his key playmaker McGuire, Kevin Sinfield long gone and Australian hooker Beau Falloon yet to even debut due to a broken toe, any success for his side will stem from desire and determination, beating their visitors into submission.
“Sometimes to win a game it will come down to individuals and a style or a gameplan, but sometimes it just comes down to the group’s desire to get the job done,” he said.
“Whether that’s us defending everything North Queensland throw at us or us doing something they can’t plan for, I am not sure, but we will certainly give it a go. A game of this stature probably deserves to have both best squads out there, but it is what it is. Because of the adversity we’ve got at the moment it is a challenge, but we’re not climbing Mount Everest here.
“It is just a game of rugby league and we’ve got to get over the top of a very good team.
“We’ve done these things in the past, but we concede it is a challenge.”
They will look to stand-in captain Rob Burrow, the 33-year-old who becomes the only Leeds player to feature in all seven of their World Club Challenges, McGuire and Jones-Buchanan’s ever-present record ended due to those aforementioned injuries.
The hooker will equal Jamie Peacock’s record of seven World Club Challenge appearances tomorrow and with victory would also draw level with his former team-mates’ total of four wins in the fixture.
Young winger Ash Handley played for Championshipp part-timers Featherstone Rovers last week but is recalled and starts.
Prop Anthony Mullally makes his competitive Leeds debut following his off-season move from West Yorkshire rivals Huddersfield Giants.
Furthermore, Josh Walters is in the squad for the first time since the 21 year-old’s surprise try-scoring cameo in last year’s Grand Final win over Wigan.
Meanwhile, Cowboys coach Paul Green takes his side into their maiden World Club Challenge maintaining the hosts’ selection issues - 19-year-old scrum-half Jordan Lilley plays only his seventh senior - will not lull them into a false sense of security.
“It would be a huge honour for us to win it, but Leeds have been a very strong team for a number of years,” he said.
“Obviously they know how to win and have a winning mentality.
“They have a very good culture and when you come up against teams like that there’s an expectation whoever wears the jersey does the job.
“We are expecting a tough game. We will be playing in conditions we are not used to and there won’t be many cheers for us.”
Leeds Rhinos: Hardaker; Handley, Watkins, Moon, Hall; Sutcliffe, Lilley; Galloway, Burrow; Cuthbertson, Ferres, Delaney, Singleton. Substitutes: Garbutt, Keinhorst, Walters, Mullally.
North Queensland Cowboys: Coote; Feldt, O’Neill, Linnett, Winterstein; Morgan, Thurston; Scott, Granville, Tamou, Cooper, Lowe, Taumalolo. Substitutes: Kostjasyn, Asiata, Bolton, Hannant.