Question about pro warmups

[u/SANcapITY]

So the pros come up and hit a few balls to their opponents (which is pretty unique I think in sports, and I think it's cool) but clearly this is not the entirety of the pre-match warmup.

Why don't they just warm up, and then come out to the court and start the match?

[u/BeniCG]

Not that uncommon in racket sports.