What can a nine-year NFL veteran learn from a nine-time Grand Slam champion? Apparently a lot.
McKinnie, who has trained with Williams in South Florida for two weeks, said he's using tennis to improve his lateral quickness and has quickly become passionate about the sport.
"It's so amazing how much you can improve," McKinnie said.
McKinnie said Williams, who owns part of the Miami Dolphins, isn't taking it easy on him. He already has dropped to about 355 pounds, according to the Pioneer Press.
"One thing I learned with Venus, you have to be ready to work for a long lesson," McKinnie said. "She tires you out."
McKinnie, who was responsible for protecting quarterback Brett Favre's blind side the last two seasons, has started 131 of 132 games since he was drafted seventh overall by the Vikings in 2002.