If you did this in your backyard, your mother would tell you to stop wasting time.

If you do this at the Yale Bowl and happen to be named Rory McIlroy, your feat will appear online.

McIlroy took his top-notch golf swing to a new venue the other day, riffing on his relationship with tennis star Caroline Wozniacki by smacking some tennis balls into the tunnels at the Yale Bowl.

It couldn't have been that hard for a golf pro, who has hit some crazy shots before, but McIlroy has to be lauded for his resourcefulness. Watch him tee off on the tennis balls below.