The Saddlers have an incredibly long injury list and have been battling for points of late with a vastly-reduced squad.
On Tuesday, they picked up their first win in 12 games and Flynn has revealed one of his players is playing through the pain.
He said: “We have a lot of possible starters out, the list goes on.
“We have players who have not been used to playing every week, like Liam Bennett, Taylor Allen and Isaac Hutchinson.
“I have one player playing who needs an operation and because of his commitment to Walsall and the togetherness of the boys, he’s putting it off until one or two come back.
“That’s the team spirit we have and it’s the fight we want to show week in, week out for Walsall.”
When asked who that player is, Flynn added: “I’m not going to tell you that am I, because opposition players might target it. I’ll tell you in due course.”
Isaac Hutchinson impressed against Northampton on Tuesday and Flynn believes with time he will perform consistently.
Flynn said: “I thought he did well. There’s obviously a lot of things he can improve on but Isaac is an intelligent footballer.
“He’s one who has not been used to week in, week out in League Two and players do have dips.
“We knew Labadie was out, but then we had Riley and Earing out as well. Jack has been out for most of the season after missing the whole of pre-season. When we’re just starting to get him back up to speed, he plays well and then he’s out for three months.
“That’s where we’re at. Even Joe Foulkes, who is out on-loan, has fractured his ankle.
“They’ve all stuck together and kept believing.”