Manchester United will cite the example of Liverpool's Javier Mascherano when they appeal against Rio Ferdinand's increased ban for violent conduct.
The 31-year-old's three-match ban was extended to four after the Football Association labelled the defender's initial appeal as "frivolous".
United say Mascherano got away without being charged for what they believe was a similar incident against Leeds.
But the ban could be increased when the appeal board meets on 12 February.
If that happens, Ferdinand will be ruled out of the Carling Cup final against Aston Villa on 28 February at Wembley.
Liverpool midfielder Mascherano caught striker Jermaine Beckford on the head back in September and Manchester United manager Sir Alex Ferguson said: "The concern is the word frivolous.
"The two most experienced referees in the Premier League are Alan Wiley and Steve Bennett.
"They are under the same controls and the same directions. One says yes (Bennett), in the case of Rio, and one says no (Wiley), in the case of Javier Mascherano against Leeds United when he punched the player in the back of the head.
"When you see that example, we don't think our appeal was frivolous."
Ferdinand only returned to action at Old Trafford against Hull for the first time in three months after recovering from a calf injury.
But after appearing to swing an arm at Hull striker Craig Fagan, the England centre-half picked up a three-match ban, which was then extended to four after the FA rejected the defender's appeal.
Because of the appeal, Ferdinand, who has made only 10 appearances for his club so far this season, was able to play in the Carling Cup semi-final win over Manchester City.
His ban began at the Emirates against Arsenal on Sunday and he will definitely miss the next Premier League matches with Portsmouth and Aston Villa.
If Ferdinand is successful in overturning the extra match ban then he will be available for the clash at Everton on 20 February.
United boss Sir Alex Ferguson expressed his displeasure last week with the disciplinary processes being used by the game's governing body.
The Scot said at the time there were "conflicting ways in how these decisions are being viewed".
He added: "I watched the game between Leyton Orient and Charlton (on Monday 25 January) and there was an elbow on the Charlton player three times as he was running with the ball.
"But nothing has happened with that. There is a lot of confusion there."
The United defence has been ravaged by injury for much of the season with Nemanja Vidic, Gary Neville, John O'Shea and Wes Brown all spending lengthy periods on the sidelines.
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