London Rollergirls Vs Gotham Girls Roller Derby All Stars - Roller Derby [Getty Images]

LEEDS, ENGLAND - JULY 12: Bonnie Thunders of Gotham Girls Roller Derby All Stars and Stefanie Mainey of London Rollergirls during the London Rollergirls vs Gotham Girls Roller Derby All Stars bout at Futsal Arena on July 12, 2014 in Leeds, England. (Photo by Shirlaine Forrest/WireImage)

WireImage Shirlaine Forrest