The controversy over Vincent Kompany's red card escalated after players from the two Manchester teams used Twitter to argue about the merits of the sending-off and Rio Ferdinand was branded a "big baby" for questioning why there was sympathy for the City captain.

Ferdinand had joined Wayne Rooney in arguing that the referee, Chris Foy, was right to show Kompany a red card that will almost certainly result in the Belgian defender serving a four-match ban. "How can there be any debate about the red card yesterday?? You leave the ground with a 2footTackle = red card,"

said Ferdinand.Rooney also hit back at Roberto Mancini's allegations that he heavily influenced Foy's decision. Rooney's message said: "Funny how people think I got kompany sent off. I'm not ref. I didn't give red card. But it was a clear red card. 2 footed tackle."

The exchange then drew a withering response from an unlikely figure, with City's reserve striker Alex Nimely posting a message on his own account, saying: "Rio Ferdinand needs to stop been a big baby."

City have lodged an appeal with the Football Association, to be heard on Tuesday, in a last attempt to prevent Kompany missing both legs of the Carling Cup semi-final against Liverpool as well as the league games against Wigan Athletic next Monday and Tottenham Hotspur the following Sunday.

The chances of the decision being overturned are slim, however, with City needing to demonstrate that Foy made a clear mistake. Only 14 out of 50 red-card appeals were successful last year and Mancini's anger was clear after the match when he accused Rooney of deliberately influencing the referee by running to him and demanding a red card. Rooney, he said, had "told him [Foy] his decision".

Sir Alex Ferguson, however, brushed aside the accusation. "I have no complaints about Wayne, I don't think it was unacceptable what he did. I think it was a natural reaction to a bad challenge from an opponent."

City's appeal is based on the fact that Kompany did not connect, or hurt, Nani when he slid into the 12th-minute tackle that had such a major say in United's 3-2 win. Yet Kompany left the floor with both feet raised and City will not be encouraged when they reflect on the case of the Wolverhampton Wanderers midfielder Nenad Milijas, whose sending-off at Arsenal last month prompted widespread criticism of the referee Stuart Atwell but ended with the player losing his appeal.

Ferguson described Kompany's tackle after the match as dangerous, arguing that Nani could easily have been injured. Kompany said on Twitter that he was "surprised" by those comments and the City defender Micah Richards, who may now have to revert from right-back to centre-half, reiterated the sense of injustice at the Etihad Stadium.

"The decision killed the whole game," he said. "We've watched it again 10 or 20 times and it was never a red card. I think for the 10 minutes before that we were battering them. Vinnie is obviously disappointed and, if it had been 11 v 11, it would have been a different game."