MANCHESTER -- Louis van Gaal is worried by Manchester United's struggle to score after a stalemate against PSV Eindhoven put them on the brink of a Champions League exit.
United need to beat Wolfsburg in Germany to reach the last 16 if PSV defeat CSKA Moscow at home on the same night.
Van Gaal's team, who have drawn 0-0 four times in their past seven matches, have only scored six times in eight games.
He said in a news conference: "Of course I am worried but I know also that goals are coming and going. It is not a consequence of good or bad performances. Today we could have scored at least three goals.
"They were not the most difficult chances but we didn't score and the next game you can score out of nothing. That is football."
Van Gaal admitted he was frustrated with both the result and the performance and identified a second-half miss by Jesse Lingard as the key moment.
"The result is disappointing because I have still the feeling we could have finished this game several times, in the first half more than the second," he added.
"But in the second we had the chance of Jesse Lingard especially. In the first half Jesse Lingard played a very good game, but we didn't play so well. In the first half I can say it was average but in the second half in spite of my changes it did not improve.
"Nevertheless we gave only one chance away in the second half so then you know at the end it is 0-0 but that is disappointing."
Van Gaal defended his decision to leave Juan Mata on the bench until the final few minutes after introducing both Ashley Young and Marouane Fellaini before the Spaniard.
"I have thought we had the best chance to win with this lineup and you shall not know if it was happening with Mata in the beginning," he responded.
Van Gaal wasn't completely sour on his side after Wednesday's draw, however, adding that he believed they can beat Wolfsburg to salvage their Champions League dream.
"We have won already our home match in Wolfsburg so why can't we win in Wolfsburg?" Van Gaal asked. "Our away average is much better than last year."
But while he is confident his charges can take three points against the Bundesliga runners-up, he admitted an opportunity was squandered at Old Trafford on Tuesday.
"We are still second so we are still in the qualifying position and we have to do it in Wolfsburg but that is more difficult," he added. "It was much more easier if we did it tonight.
"It will be very difficult because Wolfsburg are the best team in our group to play against, but it is possible.
"We have won also at home and PSV has to win against Moscow, it is not so easy."
