Angry Sir Alex Ferguson condemned Cristiano Ronaldo for allowing himself to be provoked into getting sent off in Manchester United's 1-1 draw at Portsmouth.
The Portugual international head-butted Richard Hughes who had pushed him during a goalmouth melee.
Referee Steve Bennett, a yard away from the incident, had no option but to issue a red card, earning the winger a three match-ban.
It means United go into Sunday's Manchester derby without Ronaldo, who also sits out games against Sunderland and Tottenham, Wayne Rooney - out for two months with a broken foot - and four points behind title rivals Chelsea.
Ferguson said: "Cristiano was provoked but he fell into a trap of intimidation and he has to learn from it.
"It is another big blow to lose but it has happened with him a few times. I've looked at the replay, which is inconclusive, but my take on it was that he responded to something. He should know that this is what other players do and he's got to tell himself that they are inferior to him and this is why they do it."
Ronaldo's dismissal came in the 84th minute, only seconds after Sulley Muntari received his own marching orders for a second bookable offence.
At kick-off all eyes were on Carlos Tevez, finally making his debut following his controversial switch from West Ham, and he made an impact in the 15th minute when he set up a sweet scoring strike for Paul Scholes.
Portsmouth dug in and equalised with a header from Benjani eight minutes after the break.
Although no Manchester City supporters will be lamenting Ronaldo's absence at Eastlands on Sunday, boss Sven-Goran Eriksson takes a different view.
"It is always a pity," said the former England manager. "As a fan or a spectator in front of the TV, you want to see the best players perform."
City go into the match on the back of last night's 1-0 win over Derby when Michael Johnson crashed home his first goal.
The clash of former United captains at St Andrews ended 2-2 as Roy Keane's Sunderland came from behind to thwart Steve Bruce's Birmingham. Stern John earned a point for Sunderland with his last-minute goal.