Wigan have recalled Darrell Goulding and Lee Mossop from their respective loan deals at Salford City Reds and Huddersfield Giants, after they lost three players to injury following their demolition of Harlequins on Friday.
McIlorum has impressed in recent weeks with some stand out performances, but has been diagnosed with medial ligament damage to his knee.
Harrison Hansen joins the duo on the sidelines with a suspected broken hand and coach Brian Noble admits that his side is now paper thin.
“We are pretty busted at the moment. It is a real blow to lose four players in the space of just over a week and this will now really stretch our resources. Sean, Michael and Harrison have all been playing really well for us and will be a major loss.
“We will be recalling both players [Goulding and Mossop] back to Wigan today; we are running out of bodies. Darrell and Lee will both be in contention for Friday’s home game with Catalans Dragons.”
Noble added: “I am also hugely disappointed for Tim Smith, we had hoped we could have got him back playing towards the end of the season but further tests have showed he will need surgery. Everyone at the Club wishes him well.”