Killa, 25, missed Tuesday night's tie at Coventry due to a chest infection, and the illness could see him miss one of United's most important games on the fixture list. Kyle Walker filled the centre-back position alongside skipper Chris Morgan last night (Tuesday night) and is expected to do the same again with no recognised cover.
Kevin Blackwell admits that a new centre-back arriving at Bramall Lane on a loan deal is unlikely. He said: "I doubt that we will be able to bring in a potential replacement in time, but Kyle Walker switched to central defence at Coventry and did terrifically well.
"He (Kilgallon) has a severe chest infection and was sent home late the previous night. At this stage I don't know whether he will recover in time for Friday night, but he couldn't come in on Tuesday and the doctor had to go out to Killa's home to see him."
Wednesday also have their own problems at the heart of the defence. Mark Beevers was stretchered off with an injury in the game against Middlesbrough so he's a doubt, and Darren Purse put the ball into his own net to add to the Owls' misery in the same game.
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