David Moyes has warned that none of his Manchester United squad can be certain of starting games, with the manager wanting to "use players at the right time". Moyes is also keen that Nemanja Vidic, who is the "best defender" he has worked with, signs a new contract.

The Scot was speaking after United bounced back from the humiliating 4-1 loss to Manchester City in the derby to beat Liverpool 1-0 in Wednesday's Capital One Cup tie.

The win over Liverpool came without some of Moyes's senior players and he is clear that no one is sure of their place. "There is a squad. You use the word rotation but I want to see good form," he said. "If you play it makes the job much easier. You've got to play and you've got to play well. Whatever Sir Alex had done before, you had to perform. He used players at the right time and I will try and do the same. But obviously our performance against City didn't merit people necessarily thinking they would play in the next game."

United entertain West Bromwich Albion on Saturday afternoon with Robin van Persie available following a groin problem.

When Moyes was asked if he is still at the stage of identifying his strongest side, the manager sidestepped the question, saying: "I have a lot of good players. At Manchester United I don't think you ever want to get to that. You are happy to have a group of players you can select from."

Regarding Vidic, who is 31 and in the final year of his deal, Moyes said: "I didn't know about his contract. I have not looked into it yet. I am sure the chief executive [Ed Woodward] and the club will be doing that. He is a really top centre-half. The best I have worked with."

Moyes admitted that Marouane Fellaini, the £27.5m summer signing, was off the pace against City but added it was unfair to single any individual out. "The game passed several of our players by and not just Marouane," he said. "It would be wrong to pick just one. When I took him [from Everton] he looked a little bit short and not as sharp as I wanted him. He found the tempo of the training slightly different and because of that I thought he was a little bit behind. Ideally I didn't want to rush him too quickly but the way it came around with the game I felt he would be needed. When you have only played two games for the club it is difficult to make a judgment on anybody."

Discussions with Adnan Januzaj, the 18-year-old Belgian, are yet to end in him signing a new deal, but Moyes is hopeful he will stay. "We really think an awful lot of Adnan. He is a Manchester United player. I am sure he will be [for the long-term]. We think this is the best place for producing and giving young players an opportunity. It is part of my remit to promote young players and Adnan has been promoted already and the next part is to become a regular first-team player. He is keen to stay."

Moyes also defended the form of Ashley Young, while outlining his view of Wilfried Zaha, who cost £15m but is yet to feature in a competitive game. "Ashley played against Crystal Palace [two weeks ago] and probably won us the game. He got us a penalty and was through with a chance to score. He didn't play particularly well against City but as I said you could probably have picked another half-a-dozen who didn't. Ash is fine. We will give him every chance to prove what he can do.

"Wilf has not appeared. We have not felt we have had the opportunity. The competition is hard [at United]. It is just impossible to get all these players a game at the one time. It is important Wilf gets to see the level of the training here, the level of players, the quality they have got. He is getting better which we are pleased about."

Moyes should also have Tom Cleverley available for West Brom's visit. "Tom has done a bit of training," he said. "He rocked his knee in training but he has had no reaction from it."