According to Teesside Live, Boro will definitely be without seven first-team players, while Dael Fry and Grant Hall are doubtful.
Paddy McNair, Andraz Sporar and James Lea Siliki should all be back after having spent the internation break taking part in vital World Cup qualifying games.
It’s a concern for Warnock who came under fire from a small section of the club’s support when Boro were beaten 2-0 at Hull in their last outing.
“We’ve got a nightmare injury list at the minute, but hey listen, that creates opportunities for people,” Warnock said. “We’ve got to be really positive and just have a go.
Peterborough United should make a couple of changes to their starting line-up for the visit of Sheffield Wednesday
Posh chairman Darragh MacAnthony: 'Put the hard yards in or we'll get beaten'
Peterborough United talking points: 'The diminishing value of Ronnie Edwards, a manager more impressed by hard work and performance than reputation and Bali Mumba's behaviour'
Peterborough United boss Grant McCann angered by 'disrespectful' Bali Mumba after Plymouth Argyle loss
Peterborough United linked with Ben Garrity as Port Vale boss seeks to play down link
“We’ve got some good lads at this football club and I think with just a little bit of luck everything changes.
“You saw the first goal goal down at Hull? The ball hits the post, hits the goalkeeper on the back of the head and goes in.
“We need a bit of luck like that. But we’ll keep going.”
Anfernee Dijksteel, Darnell Fisher, Marcus Browne, Sammy Ameobi and Onel Hernandez all out injured at present, while there are concerns over the fitness of recent signings James Lea Siliki and Martin Payero.
Defender Lee Peltier is suspended after acculating five cautions.