It's all on the line next Monday when Manchester United visit the Etihad.
And Souness told the People: "In every walk of life there has to be a boss and if the boss tells you to stand in the corner and count the bricks, you do it. Mancini asked him to warm up, Tevez said I've already warmed up. He said 'warm up again' and Tevez said 'no'. On every level, that's wrong.
"If that hadn't happened, Man City would be top of the League. I think they'll look back and pinpoint that incident and say we didn't win it because of that one thing.
"There's no doubt that if Tevez had played all season, instead of being back in Argentina, they'd have more points. No one can argue that it's the single biggest reason.
"In the Premier League there are a handful of great players, a hundred very good players and lots of average players. The great players do most things right, attitude and lifestyle as well. The difference now is that the groups behind that are now getting so much money, they think they're great players.
"That's where your problem lies. They think they're entitled to act in a certain way which isn't what the man in the street can relate to.
"He'd just like players to appreciate what they have. My message to any Premier League player would be 'you are playing in THE golden era of professional football, it can't get any better than this - appreciate it, because it ends too soon'.
"I think Mancini handled it well. Management has never been more difficult. Every manager deserves every penny they get.
"They have to man-manage on different terms now. That's why Alex Ferguson is so successful, he's evolved. Arsene Wenger and Harry Redknapp too. Looking back, I didn't evolve enough as a manager. I was a bit too hard on players.
"But any player who's been successful and then goes into management and finds players' attitudes are not what they should be, finds that hard to accept.
"I couldn't understand that they didn't find losing that painful. It never dimmed within me, that's why I won't manage again."