LAS VEGAS, NV - SEPTEMBER 12: Floyd Mayweather Jr. looks back at Andre Berto's corner after the sixth round of their WBC/WBA welterweight title fight at MGM Grand Garden Arena on September 12, 2015 in Las Vegas, Nevada. Mayweather retained his titles with a unanimous-decision victory. (Photo by Ethan Miller/Getty Images)

Floyd Mayweather has broken a Guinness World Record while holding an open training session in Moscow on Friday.

The boxing star invited hundreds of fans to attend the session, held in the ring at a local concert hall, and organised by Boxing Academy in association with Russian Timber Group and State Corporation Rostecheld.

The turnout far exceeded Mayweather’s expectations, with 791 people taking part in the session, and roughly 3000 spectators observing. The event broke a Guinness World Record for the amount of people who took part in the masterclass lesson.

The previous record was set in 2014, with only 508 people attending the event. The open session in Moscow was attended by official Guinness World Records judge Sofia Greenacre, who presented Mayweather with the award.