Marner posed for a snap at Toronto's Pearson Airport upon returning from the tournament, clad in a T-shirt, jeans and backwards hat, and sporting an "aw shucks" smirk that made him look much, much younger than 20 years old.
Fans started having fun with the photo, pasting Marner into situations more appropriate for a child and not one of the NHL's rising stars.
Most notably, teammate Auston Matthews changed his Twitter profile pic to Marner getting on a school bus with some elementary school classmates.
Marner also got in on the act, changing his Twitter header picture to him super-imposed on the set of the old children's show "Fraggle Rock."
While everyone is having fun now, Marner's going to get the last laugh when he turns 100 years old and still looks like he's 25.