Striker Falcao has been struggling with a calf problem, while defender Evans has been sidelined with an ankle injury.
And speaking ahead of Saturday’s Premier League clash with Hull City at Old Trafford, Van Gaal delivered an injury update on the duo.
“Evans is, of course, out with an injury that takes a lot of weeks, so he has to develop match rhythm and that’s why he had to play in the second team,” Van Gaal told MUTV.
“He played 60 minutes but then you don’t already have the match rhythm of the Premier League. He is fit to play but not for the Premier League.
“Falcao is not ready. It is the same thing with Evans. When you are out of the running for so long and not training with your fellow players and only running because of the injury, one week of training sessions is not sufficient to develop match rhythm.
“I need strikers now, so maybe he is in the 18.”
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