Image Credit: USA Today Sports

Cris “Cyborg” Justino is booked to fight one of the most decorated boxers to ever transition into MMA, Holly Holm, and as a result, she’s been sparring with another of the planet’s top female boxers.

“Cyborg” is set to defend her featherweight title against Holm on December 30th, at UFC 219. Recently TMZ Sports posted the video below, which shows the UFC champ sparring Mia St. John, who won titles in multiple divisions.

St. John retired from pro boxing in 2016 having gone 49-14-2. Holm also won titles in different divisions, before moving over to pro MMA.

UFC 219 will be hosted by the T-Mobile Arena in Las Vegas, Nevada.