Tennis pro Jack Sock shows sportsmanship

American Jack Sock played Australian Lleyton Hewitt Tuesday in Perth, Australia.

Playing in the Hopman Cup - an annual international team indoor tennis tournament - Sock was at a distinct disadvantage on multiple fronts.

So how did Sock win over the Australian fans at Perth Arena? 

Watch below:

Sock, ranked 26th in the world, surprised Hewitt by pointing out the incorrect call by the official. At first, Hewitt looks puzzled.

It was, after all, an important point in the match: Hewitt was trailing 4-5 in the first set. 

But Sock was certain the serve was in, and he encouraged Hewitt to challenge. Later, a replay confirmed Sock was correct.

Hewitt won the match 7-5, 6-4. But Sock's act was trumpeted worldwide.

"That was in, if you want to challenge it." "Was it?" "Yeah." Talk about great sportsmanship. Bravo, Jack Sock: https://t.co/2jg9Qd12r1

Jack Sock shows amazing sportsmanship to Lleyton Hewitt https://t.co/WBqHei6YSI pic.twitter.com/DzddSsciSV

Though defeated, Sock emerged as a winner, and displayed sportsmanship for young athletes - and old ones - the world over. 

Photo Credit: SB Nation , Channel 7