Louis van Gaal described Marcus Rashford as a "special talent" after he scored two goals in Manchester United's 3-2 victory over Arsenal on Sunday.
The teenager - making his Premier League debut after netting a Europa League brace on Thursday - struck two goals in the space of three first-half minutes to put United in control at Old Trafford.
Danny Welbeck pulled one back for Arsenal, but Ander Herrera re-established the cushion and Mesut Ozil's reply was not enough to salvage anything for the title-chasing visirors.
And Van Gaal singled out Rashford for praise afterwards.
"That is why we have a small selection because then you can give youngsters a chance," he is quoted as saying by BBC Sport. "A big selection means they don't get a chance.
"The experience of mine is youngsters always play well the first match. The second match is different. Marcus played well in both matches, so he is a special talent."
Asked if he recalled other memorable debuts, Van Gaal added: "I can imagine a lot of them. Patrick Kluivert makes the winning goal [for Ajax] in the Super Cup in the Netherlands. Xavi, fantastic against I think Valladolid [for Barcelona] and also Thomas Muller a fantastic debut. He was playing in the second team [for Bayern Munich]."
The Dutchman was satisfied with the wider team performance, which saw United climb back to fifth in the Premier League and deal the Gunners' hopes of being crowned champions a blow.
"The performance and the result [was pleasing], when you are playing against one of the best Premier League teams and can play with such ambition and performance," he added.
"We played very high in the first half, that is risky against a team like Arsenal but we changed things in the second half and were very compact."
Van Gaal dramatically threw himself to the ground late on in a bid to make a point to the officials and, while he insists he does not regret the move, he concedes it may have been disrespectful to the referee.
"It's emotion," he told Sky Sports. "I don't let myself go too much, but my emotion was a little bit too high, so I have apologised to the referee, the linesman and the fourth official. It is already resolved."