The Owls are at Derby County knowing victory for them will keep them in the Championship if neighbours Rotherham United fail to beat Cardiff City. Any other combination of results will send them into League One.
Derby are also in danger of relegation but a win will keep them safe or a draw if Rotherham fail to pick up three points.
Manager Moore contracted Covid-19 at the start of April and missed three games. He returned for the defeat at home to Swansea City but felt ill afterwards and has been missing since with pneumonia and blood clots on the lung.
He could, though, be at Pride Park. Whether he is and in what capacity will be decided late on.
"He's improving day by day," said Moore's assistant, Jamie Moore, who has been taking the team in his absence. "He's much, much better in himself but still he's got a long way to be fully recovered.
"He's contributed lots. He's been in and around the training ground, physically he's been here which has been good for the players to see him and for him to have a chat with the players. It's been good to have him around.
"He's just been talking to the players about belief and being positive and looking forward to the game. We've had a good working week and to implement the stuff we've been working on."
Naturally, Moore's involvement will depend entirely on his health on Saturday morning, and how he feels after his time on the training ground. Smith was not ruling out him actually taking the team but clearly an appearance of any description will lift Wednesday moral.e
"We're going to see how he is," said Smith. "It's day by day.
"We'll see how he reacts after every day basically but fingers crossed he'll be there.
"I can't say he's going to do this or that because he just doesn't know. Potentially he could be in the director's box, depending on how he is.
"I'm sure it will have a positive effect, most definitely."
Massimo Luongo and Joost van Aken have both been back in training this week too and whilst the game will come too soon for the latter, who has not played since December, midfielder Luongo could have a part to play from the bench.
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