It's been a tough month for Floyd Mayweather Jr. The boxing icon, whose ex-girlfriend and mother of his three children died suddenly last week, lost another very close member of his family days later: his uncle and trainer, Roger Mayweather.

The senior Mayweather was a champion boxer in his own right, and was referred to as "Black Mamba" before Kobe Bryant adopted the nickname. Sadly, he reportedly suffered extensive brain injuries during his time in the ring, and the effects of that could have resulted in his death at 58.

Floyd was reportedly deeply affected by the loss of his uncle, who was a big part of his path to becoming a world champ. Now, Floyd has taken to Instagram to pay tribute to Roger with a series of throwback photos, just like he did for his ex-girlfriend Josie Harris just days ago:

The official cause of Roger's death has not been revealed, though, according to Floyd, he had been suffering for several years. As for Josie Harris, her death is a mystery with no evidence of drugs, suicide or a struggle. According to the Los Angeles County Coroner's Office, her official cause of death has been "deferred" pending "additional investigation."