Moyes secured the club-record signing of Mata from Chelsea for �37.1 million ($61.2 million, 44.8 million euros) last week, describing the Spaniard's arrival as the start of his rebuilding process at Old Trafford.

United were linked with a move for Bayern Munich's Toni Kroos after Moyes watched the Germany international midfielder, 24, last week.

But 12 hours before the January transfer deadline was due to fall, Moyes declared United's business finished and said that he would wait until the end of the season before adding any more players.

"You can stand the cameras (at the gates of the training ground) down; they won't be required. We've done our business and we'll get on with it," he said.

"There's no disappointment because I said at the start of the window that we probably wouldn't do much business in January. That's for lots of different reasons, not any one thing."

Moyes saw strikers Robin van Persie and Wayne Rooney both return from injury in Tuesday's 2-0 win over Cardiff City.

Van Persie, who played for an hour, had been out since December 10 with a thigh injury and Rooney had been absent since January 1.

Moyes, who revealed that midfielder Marouane Fellaini is also close to a return from his wrist injury, said that he will continue to ease Rooney and Van Persie back into action gently.

"We've got to be careful with them both because they're both returning," he said. "Wayne only had 30 minutes and Robin had about 60 minutes, so we're mindful of that and we'll make sure they're ready.

"We're a bit more concerned because Robin's been out longer. Wayne's been out for a shorter period so we have to manage them and do it right, but I've got them back and it's great to have them.

"Felli is on the fringes of things and we need to get him some match practice, but he's close to it as well."

United have allowed Wilfried Zaha to join Cardiff on loan for the rest of season and Moyes is looking forward to seeing how the winger gets on in the Premier League.

Zaha, 21, has made just two substitute appearances since joining United from Crystal Palace last year.

"I said at the start of the season, if I could get him the games, I'd keep him in, and if I couldn't, I would get him some games on loan," Moyes said.

"We had a few clubs that wanted him on loan, but we felt Cardiff was the right choice for him. Hopefully he'll go and get those games and show what he can do in the Premier League and be ready to come back to us at the end of the season."

Mata had a hand in both of the goals against Cardiff, but while Moyes has been pleased with the midfielder's start at United, the manager warned against expecting too much from the Spain international.

"He's everything I thought he was," Moyes said. "He's a terrific footballer and a really good lad to work with. He's settled in very well and quickly and played well and helped us in the game.

"We needed someone to come into the team and make a difference right away and know the Premier League and it's never easy, but I'm also wary we have to give him time to settle in. I was pleased with his first game."