Sir Alex Ferguson has accused referees of victimising Cristiano Ronaldo following his booking for diving during Manchester United's Carling Cup Final victory over Tottenham.
The Portugal winger was booked in the second half of Sunday's Wembley showpiece which United won on spot-kicks for going to ground in the penalty area.
Television replays suggested there had been contact between Ronaldo and Spurs captain Ledley King and Ferguson was annoyed that referee Chris Foy opted to issue a yellow card for simulation.
The booking was Ronaldo's fifth of the season but he will not face a ban as the card was issued after the February 28 amnesty when suspensions are no longer issued.
"It's disappointing, not so much because he didn't give the penalty but because he booked Cristiano," Ferguson told MUTV.
"You can't appeal against a yellow card so that has been added to Cristiano's record now.
"That's twice it's happened this season. It's too easy an option for these referees.
"He (Foy) should be challenged on why he gave the yellow card."