Olympic champion Simone Biles announced Riders Up at the 151st Kentucky Derby. Here's what social media users thought of her call.

Simone Biles will be serving as the "Riders Up" announce for Kentucky Derby 151. Here's who else has done it over the years.

Kentucky Derby 151 is in the books, and your winner is Sovereignty. As someone who didn't watch one second of the event. I have no idea if that was an upset or not. Still, the derby appears to be a big deal to those who can afford to get in.