WATCH: Pro Tennis Player Gives Away a Point By Urging Opponent to Challenge Ref's Blown Call

Jack Sock, a 23-year-old American professional tennis player from Kansas, exhibits true sportsmanship.

Jack Sock and Lleyton Hewitt

Jack Sock is a 23-year-old American professional tennis player.

Lleyton Hewitt is a 34-year-old Australian professional tennis player.

The two met last night in an early-round game of the Hopman Cup, an annual tennis tournament held in Perth, Australia. Hewitt was up on Sock 30-love when he unleashed a beautiful serve that looked like it might have caught the line for a point.

The official ruled it out.

What happened next was rather unusual:

Yep, Sock explicitly told Hewitt to challenge the official's ruling because he knew the ball hit the line.

You don't see that every day! I'm not going to say Sock could've let this one slide, but he did end up losing the game and the match to Hewitt. Sock was raised in Kansas, so maybe his midwestern values kicked in and took over. Do you think he baked Hewitt an apple pie after the game?

But seriously, good for Sock for this display of sportsmanship. He'd be an awful politician, but he seems like a super nice guy.

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