This tennis player produced one of the greatest acts of sportsmanship we've ever seen

Tennis has a new hero.

While the antics of Nick Kyrgios may have sullied the reputation of the men’s game of late, 23-year-old US player Jack Sock has just restored our faith in the sport entirely with one monumental act of sportsmanship during a match in Australia yesterday.

5-4 up in a first set against 34-year-old veteran Leyton Hewitt in Perth’s Hopman Cup, Sock stunned everyone in attendance by telling the home favourite to challenge a serve declared “out” - which was actually in.

In the sparsely believable scenes that followed, the home favourite’s reaction said it all: the act almost rendering him speechless, it took a moment for it to sink in before Hewitt took his advice, looking up at the equally bemused umpire and challenging the call, which of course he won. Evoking other great sporting acts of kindness (Di Canio anyone?), this moment will live long in the memory

Unfortunately for Mr Nice Guy, Hewitt went on to take the game, soon the set and later the match, winning 7-5, 6-4 to progress to the next round.

Maybe he wishes he put a sock in it now.