Louis van Gaal is convinced Manchester United can discover their killer instinct in front of goal in order to avoid an early exit from the Champions League.

United are facing elimination from the competition at the group stage for just the fourth time if their patched-up side fails to beat Wolfsburg.

If they draw or lose, United will have to rely on PSV Eindhoven slipping up at home to CSKA Moscow - who have already been eliminated - to make it through to the last 16.

On the face of it, United do not stand a good chance of progressing.

The Red Devils have scored just seven times in their last ten matches, but their manager is confident his players will find their scoring boots again at the Volkswagen Arena.

"I have the experience as a manager that the goals shall come," Van Gaal said. "When you are creating chances at the end you shall finish those kind of chances.

"That's why we have that belief. It's a matter of time and I hope we can prove it."

As the only striker in a threadbare squad, the responsibility for scoring will fall on the shoulders of Anthony Martial, who has scored just once in his last 13 matches.

"He is very talented but he is just 20 years old," Van Gaal said of the forward, who scored four goals in his first four matches following a £36million transfer from Monaco in September.

"We have to give him time and that's always difficult when you are playing for a team like Manchester United because the expectations are very high.

"But I am very convinced that he will continue with his performances, and that he shall score at the right moment again.

"You cannot expect of a 20-year-old player coming to the Premier League that he scores every week.

"I didn't expect it either. When he came he was accelerating in the start of his campaign at Manchester United. I know that and I have to explain it to everybody because he doesn't need that pressure to score every match."

Van Gaal concedes dropping into the Europa League would be a big blow for the three-time European Champions.

"It's very important for the club to continue in the Champions League, and also for the players," Van Gaal said.

"They want to show their qualities at the highest podium. That's why it's important (we qualify)."

United will be without Wayne Rooney, Marcos Rojo, Luke Shaw, Antonio Valencia, Ander Herrera, Phil Jones and Morgan Schneiderlin for the do-or-die game.

Nick Powell, who has only played one game for United in the last three years, Sean Goss, who is yet to make his debut, and 18-year-old defender Cameron Borthwick-Jackson are in the 19-man party that has flown to Germany.

Guillermo Varela made his debut in the 0-0 draw against West Ham on Saturday but could be thrown into the starting XI on Tuesday.

The United squad could be depleted further for Saturday's game at Bournemouth after Bastian Schweinsteiger was charged with violent conduct for an alleged elbow on Winston Reid against West Ham.

The German is facing a three-match ban if found guilty. He has until noon on Thursday to respond to the charge.