WATCH: De Minaur, Tsitsipas try boxing to mixed results

The offseason is first a time for holidays and relaxation, and then a period of intense training. Some of the young players on the ATP and WTA tour have spiced things up by throwing some punches instead of the usual gym regimes.

There's been Alex de Minaur's lightning quick feet paying off in the ring:

Then there's Russia's Dayana Yastremska's passionate fury:

And most recently, the Patrick Mouratoglou Academy released footage of Stefanos Tsitsipas giving the sport a try—though he seemed more than a little out of his comfort zone:

The 2019 season kicks off the earliest for Tsitsipas as he will represent Greece alongside Maria Sakkari at the Hopman Cup.