Photo gallery: Djokovic preps for Tsonga

MELBOURNE, Australia – On an off day after his impressive first-round victory over American qualifier Mitchell Krueger, No. 1 Novak Djokovic hit the practice court.

His training partner was up-and-coming young Aussie Alexei Popyrin, a 19-year-old ranked No. 149 – near his career best.

It’s astonishing to think that Popyrin is just six months younger than countryman Alex de Minaur, and four months younger than Denis Shapovalov.

And yet, he’s more or less where he should be, while de Minaur and Shapovalov are highly precocious.

Second round rematch of 2008 final

Djokovic knows Tsonga well, having played him 22 times and boasting a 16-6 record against him.

The first time they met was in the 2008 Australian Open final – Djokovic’s first career Grand Slam title. So there’s some illustrious history.

But they haven’t even met since the 2016 US Open – nearly 2 1/2 years ago.

And a lot has changed since then.

“It feels like a lot has happened for both of us. He also struggled with injuries lately. It’s good to see him playing well. It’s good to see him back,” Djokovic said.

“He’s another great player, champion, someone that has been very successful in the past, established top-10 player, played Grand Slam final. Just very powerful, serve, forehand, big weapons. I know what to expect. I’ve played him many times. I lost to him, as well.”

Here’s what the practice session looked like.