Djokovic just beat Nadal to win at Wimbledon! And if there's a professional athlete out there in need of a primer on how to behave--win or lose, just watch the trophy ceremony on the field post match. After playing their hearts out, these world CLASS athletes graciously received their awards, shook hands, and sincerely and publicly expressed respect for their competitors. There was never a moment of braggadocio. No silly victory dances in the end zone. No rabid fan hatred spewing onto the court. Their decorum certainly won them the respect of the crowd and no doubt the millions of viewers watching around the world.
It is clear these sentiments were not merely false show on the spur of the moment, but rather the result of longstanding relationships cultivated on the road among a group of athletes traveling the world together; certainly they do not all like each other, but it's clear they have at least cultivated professional relationships that allow them to behave like gentlemen in the context of the sport. It's clearly "not cool" for them to behave otherwise, and raises the level of the game for everyone, competitor and spectator alike.
It's called "sportsmanship."