Moors damaged a knee in last Sunday’s Betfred Super League win over Warrington Wolves.
And coach Daryl Powell said initial fears over the seriousness of the injury have been confirmed.
“He will be up to 10 weeks, maybe a little bit longer,” Powell said. “We’re not certain exactly, but he has got a high grade two mcl (medial cruciate ligament) knee injury.
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“It’s a tough one for him and we’ve had a couple of those recently with Matt Cook getting one as well. Some of our big men in the middle will do a lot of hard work, there’s going to be a few guys need to step up.”
Tigers’ first game without Moors will be Sunday’s Ladbrokes Challenge Cup quarter-final at Hull. Powell was due to name his squad this afternoon and is confident they can cope.
“It is what it is,” he said. “We’ve been reasonably lucky with injuries this year so we’re not going to worry too much about that.
“He has been a big player and done some great things, but we’ve got a strong squad and we are looking forward to the challenge.
“The 17 who take to the field are all good players, they all know exactly what they’re doing and they just have to deliver on the day.”
Despite the latest injury setback Powell insisted Tigers are “in a good place” ahead of Sunday’s tie.
He added: “Since Hull beat us [in April] we’ve won eight straight. There’s a lot of confidence about the players and what they can deliver.
“We’ve been defending pretty well – our average is about 15 [points conceded] or just over so we are achieving the goals we set in that area.
“But this is a different entity. It is an important game, it’s knockout and if you get beaten that’s it, you don’t continue in the Challenge Cup.
“We don’t want that to happen, but we recognise Hull will be desperate to win as well. They are the holders, they are at home and I think they’ll be slight favourites.
“But ultimately it’s about the performance on the day. We are mindful we need to turn up and have great discipline about us and put them under pressure, which we didn’t do last time we played them.”