Caroline Wozniacki On Richard Branson's Island

Here's Caroline Wozniacki proving the life of a pro tennis player is super, super tough ... taking the time to go full vacay mode while on Richard Branson's private island.

Wozniacki and fellow tennis star Nicole Gibbs are hanging out on Necker Island for the Necker Cup ... a super exclusive Pro-Am tennis tournament.

(Fun Fact: Mike Tyson's tennis prodigy daughter is also there!)

We're not sure if it's work or play ... but judging by the video of Gibbs teeing off into a pristine ocean view (and almost hitting a boat!) it looks like a little bit of both.