Manchester United manager Louis van Gaal says that he has no concerns about potentially throwing more youngsters into his squad for Saturday's home game against West Ham United.

A new thigh injury to Chris Smalling means that all of Van Gaal's recognised right-sided centre-backs are now unavailable, while fellow central defender Tyler Blackett is suspended.

The United manager is set to bring Marcos Rojo into central defence from left-back against West Ham and he could be partnered by either utility player Daley Blind or central midfielder Darren Fletcher.

Youngster Paddy McNair could also be involved in the squad, but Van Gaal has no doubts about pitching the 19-year-old into the team for a one-off game.

"Young players are always ready. They have hunger to play. Manchester United's youth education has a certain level that can provide that," he said.

"It's a big difference (stepping up to the Premier League), but in one game you can show yourself better than playing regularly."

He added: "I don't take risks. You have to be fit, and I always trust younger players."

Michael Carrick, Ashley Young, Marouane Fellaini and Jesse Lingard are also absent as Van Gaal looks for a second win of the season.

United have conceded 12 goals in their six matches to date, but Van Gaal feels the 4-0 defeat at Milton Keynes Dons in the League Cup and last weekend's 5-3 loss at Leicester City have created inaccurate perceptions of his team's defending.

"It's not a regular occurrence," said the Dutchman.

"When you see our figures in the Premier League, except this match (against Leicester), then we are defending well. The average (of goals conceded per game) is less than one and we scored a lot of goals."

United were beaten seven times on their own turf in the Premier League last season and Van Gaal accepts that reversing that trend will be key to transforming his team's fortunes.

They have already lost once at home -- a 2-1 defeat by Swansea City on the season's opening day -- and Van Gaal is determined to improve results at Old Trafford.

"It's very important. It's a question that you already know the answer to," he said. "It's very important to win your home matches. I can't deny that."

West Ham manager Sam Allardyce admits he fears the reaction from Van Gaal's side following their astonishing defeat at Leicester, which saw them toss away a two-goal lead for the first time in the Premier League.

West Ham head north buoyed by last weekend's 3-1 home victory over Liverpool, but Allardyce admits he will be happy if his side can leave with a point.

"I'm thinking a backlash," he said. "I think that because of the determination of the Man United players and the fact they are playing at Old Trafford.

"I know there are quite a lot of new players playing there, but certainly the demand of Manchester United is huge and they'll be really fired up to make sure that they try and perform like they did against QPR and beat us.

"They will be pretty down about that performance they gave at Leicester and they will be hurting and they know the only way they can put that right is to get out onto the field and punish us for it.

"So we will have to be careful about that. A draw would be great for me. Anything more than a draw would be outstanding as far as I'm concerned."

West Ham will be without Cheikhou Kouyate, who has been ruled out for six weeks with a groin strain, and Kevin Nolan, who has returned to training after a shoulder injury but is short of match fitness.