Shrewsbury's Tom Flanagan a doubt for the FA Cup game against Sunderland

The defender went off in the 17th minute after he took a knee to his side – and the boss revealed he has since undergone an MRI scan on his liver due to the severity of the impact.

He said: “He’s not looking the best at the moment.

“He ended up spending Sunday in a Birmingham hospital having an MRI scan for damage on his liver and swelling on his side.

“We did not even get a free-kick for that.

“He got a knee in there, it was a blatant foul. There were two fouls on Tom Flanagan.”

The defender has not had much luck recently – he was ruled out of Town’s Boxing Day clash at Cambridge 20 minutes before kick-off after suffering from illness.

And the defender is now a doubt for the FA Cup clash against the Black Cats as he battles to overcome the problem to face his former club.

Meanwhile, Steve Cotterill has praised the work done behind the scenes by staff at the club after they had their second red card appeal of the week upheld.

Matthew Pennington was the latest Town player to have a red card overturned by the FA after he was sent off in the 22nd minute for an alleged handball.

But after further inspection, it was revealed the ball actually struck Pennington’s shoulder, so the sending-off and the award of a spot-kick were the wrong calls by the officials.

And Cotterill praised the work behind scenes by the club’s media team, chief executive Brian Caldwell and club secretary Jayne Bebb.

He said: “Let me tell you now, it is huge to win an appeal, it is really difficult. They go to the letter of the law, even if it is accidental it is the letter of the law. It is lucky that we have ended up with good footage from our media guys, that end up getting hold of it and all the stills.

“Our media guys have done a really good job of producing what we really needed in those vital moments.

“We have put a lot of hard work into that over the past week because of Luke’s as well.

“It’s been a good job by all on that – Brian and Jayne (club secretary Jayne Bebb). There has been a lot of input and a lot of help. It has been a real team effort to get those appeals upheld.”

And Cotterill feels his side have been very unfortunate with decisions not going there way this season.

He continued: “To get three red cards on the spin, I don’t think I’ve had that in 28 years of management.

“I think the one with Ryan Bowman (at Cambridge on Boxing Day) – we probably could have appealed that one as well.

“But the footage from the game was poor, we didn’t have the right angles to show it was an obvious wrong decision from the referee, otherwise we’d probably have had a go at that one as well.

“The others, Luke Leahy – how you can get sent off for putting your hand on the back of someone’s neck? I can’t believe what the referee has seen.

“And at the weekend, when you look at that one, the ball hitting Matthew Pennington on the shoulder – you only have to look at the rules and it shows in green (on a diagram) where it is handball and a penalty.

“A red card? The penalty is bad enough. But a red card on the back off it - I don’t get it, I really don’t.

“It’s happened and it’s happened time and time again to us. I can’t believe they can get it so badly wrong.

“The referee on Saturday didn’t give himself time to think about it. To win an appeal, first and foremost you have got to be right.

“Thankfully we have won the appeals.”