Angry Manchester City boss Kevin Keegan launched into Joey Barton after the midfielder narrowly escaped dismissal in the friendly at Doncaster.
Barton sparked a 10-man brawl by hacking at Rovers' Paul Green, forcing Keegan to replace him at half-time.
Keegan said: "I told him the truth - you either play football or you come off. There is no choice.
"If we had been away from home in the Premiership and he did that, he would have been sent off."
Barton clashed with Rovers' skipper John Doolan in the opening minutes of the 1-1 draw at Belle Vue.
The spiky City midfielder then launched into Green as he attempted to shield the ball between his legs.
Barton was yellow-carded, along with Rovers goalscorer Leo Fortune-West for a retaliatory tackle which left the City midfielder limping.
As Rovers marked Barton out for special treatment, Keegan refused to show any sympathy for his young midfielder.
Keegan said: "He thinks he can look after himself but when you get in this division and
start doing things like that, people sort you out - and that's what they did.
"I don't want to stop him being tenacious but I do want him focused on what football is all about.
"I have a problem with any player who just wants to go out and be physical all the time. There is no future in that.
"He has a nasty knock but hopefully he will learn from it because if he wants
to fight, there are a lot of pretty tough players out there."
In the 10 minutes following Barton's ill-advised tackle, Danny Mills, Steve
McManaman and Richard Dunne all looked like getting dragged into petty feuds but
fortunately the game settled down once the half hour mark passed.