Van Gaal revealed on Friday that summer loan signing Falcao could be included in United’s matchday squad when the Red Devils host Hull City at Old Trafford on Saturday afternoon.
Van Persie, 31, has been struggling to find consistent goal-scoring form in recent weeks and has only managed three Premier League goals so far this term.
And when asked if Falcao’s return will put pressure on Van Persie, Van Gaal replied: “Every player in my selection has to fight for his position and I shall always take the best of the players, and it must also be suitable for the mix of players.
“So, it is also an obligation of a player that he does that.”
Van Gaal’s Manchester United side are fourth in the Premier League table heading into Saturday’s game.
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