Rhinos were without 12 of their senior squad when they were beaten 26-18 by St Helens in the Betfred Challenge Cup.
Adding to their problems, substitute forward King Vuniyayawa was knocked out just three minutes into his debut, which will rule him out of Thursday’s home clash with Wigan Warriors.
Leeds are also likely to be without fellow front-rower Zane Tetevano following his red card for a late challenge on Saints half-back Theo Fages.
The incident will be studied by the RFL’s match review panel today.
Rhinos’ problems are centred on their backs, with all five of their specialist half-backs - Luke Gale (broken thumb), Rob Lui (quad muscle), Richie Myler (hamstring), Callum McLelland (groin) and Kye Eastmond - unavailable for the Cup tie, along with two Liam Sutcliffe (knee) who played at stand-off in the opening two games of this season.
Two forwards, Rhyse Martin and Cameron Smith, played at six and seven against Saints, but The Yorkshire Evening Post understands Eastmond - who was signed last month, but has yet to make his debut - could come into consideration this week.
Agar admitted he has never experienced a situation where all a club’s spine players - and most of their first-choice backs - are ruled out at the same time.
But he insisted: “The thing with our injuries is, there’s some light at the end of the tunnel - it’s not long-term.”
So many casualties are obviously a concern just three games into the season, but Agar stressed: “The injuries have come about in very different ways.
“Some are from last season, a number of them are from our first two league games and our trial game, which have been broken bones, contact injuries.
“I don’t want to put too many numbers on it, but we will have a couple returning and available [for Thursday] and I think the week after, where we are at the moment, we should have six or seven returning then.”
Agar was “proud of the performance from start to finish” against Saints. Leeds trailed only 8-6 at half-time and then, after Tetevano’s dismissal, hit back from 20-6 down to trail only 20-18 going into the final nine minutes.
Agar reflected: “We need to keep fighting hard at this moment in time, when we are a little bit unbalanced, but if we can set that as a benchmark for effort and commitment and how hard we are going to defend, we won’t be too far wrong.
“We are out of the Cup and we wanted to defend the Cup, but there were some circumstances.I thought we had to overcome a number of hurdles during the game, but we can certainly pull out some positives and let that be a benchmark for effort and small things like how we got off our line and how hard we tackled.
“I thought we really went after them defensively and when things didn’t go right we tried to cover each other up, through sheer effort. I thought we shut a number of opportunities down for them through that.
“I really applaud our guys, take my hat off to them for the effort. They are gutted they’ve lost the game, but at the same time they know how much they’ve put into it and where that effort took them in some very difficult circumstances.”
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