The Red Devils completed their final preparations for their Champions League trip to Russia at their own Carrington training ground complex on Tuesday morning before jetting off to Moscow.
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Van Gaal was quizzed on United’s decision to train in England before the flight at his pre-match news conference on Tuesday night.
And the United boss explained: “We trained in Manchester today because of the logistics and the way we have to prepare for matches.
“We were told that there would be traffic jams in Moscow so we thought it would be better to train at home on our training ground.
“My preference is to train here, because then the players know the circumstances and where they have to play, but in this case we decided to train in Manchester.”
United have lost their last three away games in the Champions League proper, although they did win 4-0 at Club Brugge in the play-offs.
The Red Devils, who are third in the Premier League table and two points behind Manchester City, have won only one of seven matches, home and away, against Russian opposition.
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