Jelena reprimands Novak Djokovic on Facebook Live

"A funny thing happened on Facebook" (if you fast forward to the last 30 seconds of Novak Djokovic's training video). That's a reusable saying as far as social media goes, but a surprising one in light of Novak and Jelena Djokovic's involvement in this case.

In the 12-plus–minute clip, Jelena filmed her husband's tennis practice and then balked at his desire to take her smartphone and speak directly to fans.

"No, I like to take the camera, it’s nice," Djokovic says. "It makes me feel more into it, more I guess, friendly."

Come for the awkwardness. Stay for Jelena's shocked realization near the end that the live video was still running.

Not one to simply have her phone taken away after such dedicated filming for nearly a quarter of an hour, Jelena sternly gave her video subject a piece of her mind (in Serbian).

"How are you behaving yourself? For heaven's sake," she says. "'Thank you, love. Thank you.' Isn’t that what you should be saying?"

"I just wanted to film," Djokovic says, before trailing off. "I don't know why you wanted..."

Thus Jelena put Novak, the champion of 12 Grand Slams, firmly in his place. Looks like the world No. 2 will think twice before swiping her cellphone again.

Follow Jon on Twitter @jonscott9.