Ryan Giggs, Manchester United
Premiership Update : Manchester United v Swansea City Tickets
However veteran Red Devils star Ryan Giggs says United are still confident of reaching the Capital One Cup final.
The FA will probe David Moyes' comments following the first-leg Capital One Cup battle.
Man United manager Moyes made a scathing attack on referee Andre Marriner after United's defeat in the Capital One Cup semi-final.
Moyes was furious over the decision to award Sunderland a penalty after Tom Cleverley's poor tackle on Adam Johnson, with Fabio Borini firing home the resulting spot-kick in the 64th minute.
Moyes was also angered by the free-kick given to Sunderland for Jonny Evans' aerial clash with Steven Fletcher, with Ryan Giggs scoring his own goal.
With Moyes in charge, United are having the worst run of form since May 2001 as they suffered a third successive defeat.
"We had a player booked for the same challenge the other day, for doing the same thing. It's up to the referees, they're making their minds up," remarked Moyes. "It looks as if we're having to play them as well as the opposition at the moment. It's really terrible, it really is, we're actually beginning to laugh at them."
"We just need to keep going, we didn't do an awful lot wrong. We conceded a terrible first goal from the free-kick, but it was never a free-kick, it was our free-kick.
"I thought the referee was going to blow in our direction. I couldn't believe he gave a free-kick for that Jonny Evans challenge on Fletcher in the air, it was just a terrible decision.
"We've got an opposition to play and sometimes we've got other people to play at the moment."
Man United are currently 11 points off the lead in the Premier League and are out of the FA Cup.
Sir Alex Ferguson's successor insists that he is relishing the opportunity to secure a trip to Wembley when the second leg takes place at Old Trafford on January 22.
"This is a two-legged game, and I'm really looking forward to the second leg now.
"Our crowd were unbelievable tonight, the support they gave the team and me was terrific. The players deserved it because they did well enough to get a result.
"We'll do everything that we can to try and get it right. The players put in a strong performance tonight, it just didn't quite come off. It's not far away and it's coming, I can sense it."
Next United host the Swans at Old Trafford.
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