Sports Illustrated is reporting that the 21-year-old will be joining Mayweather's entourage for the boxing match.
No word on why Bieber is accompanying Mayweather, or whether he's receiving any compensation for his appearance, but TMZ is reporting that the two have been friends for years.
Bieber joined Mayweather as he made his way to the ring for his May 5, 2012 bout with Miguel Cotto. The Biebs was also present at a recent Mayweather-Pacquiao press conference.
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