Colin Todd believes Sunderland boss Roy Keane has the same presence as managerial legend Brian Clough.
Todd worked with Clough at Derby County and told The Journal: "Brian was a one-off, anyone who played under him had to be influenced.
"People say Roy is the new Cloughie or that he has taken bits that he learned from Cloughie and it doesn't surprise me. There was a definite aura about Clough and I think there's probably a bit of the same thing about Roy Keane as well.
"He's worked under Clough and Sir Alex Ferguson and there are not two better British managers in the modern era than them.
"I don't think there would have been a Brian Clough in the modern era, to be honest. I'm not sure his methods would have worked now, so maybe Roy has had to adapt what he learned when he was at Nottingham Forest.
"It will be interesting to see how Roy's managerial career progresses. But I'm sure that, like me, Roy has been influenced by working with Brian."