Van Gaal hauled Van Persie off 15 minutes from the end of Sunday nightâ€™s dramatic 2-1 win over Mexico and watched as his replacement Klaas-Jan Huntelaar set up one goal and score the winner from the penalty spot.
"The substitution of Van Persie was tactical.
"Letâ€™s not forget before he joined team he was recovering from an injury. Itâ€™s difficult for him to keep up 90 minutes especially in these conditions.
"Anyway, this trainer wants to win. So he makes the changes and the substitutions he needs. Itâ€™s simple. Nothing else matters."
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