Maybe he didn’t lie but just didn’t tell.
For example, I perform at every thing from kid’s birthday parties to bachelor parties and many corporate events. When asked for references I offer only what pertains to the job I am applying for. The other references are not in the same industry so I don’t purposely hide it but I don’t offer it either. Maybe he was doing the same. Only mentioning his tennis credits because it’s a tennis job. If he has enough references and credits to his tennis career than I don’t think he mislead anyone.
Hugs and Hissessss,
Maria