There are not too many options with tennis based outfits,but here are links to a few choices.
It is puzzling as to what is going on in this one with none other than number one Novak Djokovic. Back in 2008, Djokovic dons this Zorro mask and and appears to be getting into it a little too much.
This tennis ball costume is good for hiding the figure but how does one get out of it for maybe like going to the restroom?
Violence is always just a second away in tennis and this outfit captures that idea in a great way. It looks like might be a bit tricky to navigate at a crowded party.
And if you are really scrapping for an idea, this shirt will do and it can almost be worn year round.
In closing, check out this zombie tennis video. Sadly there have been players who have moved this way in real matches.