The credibility of Roger Mayweather as a trainer is because he was a good boxer.

http://en.wikipedia.org/wiki/Roger_Mayweather
Roger Mayweather
Statistics
Real name Roger L. Mayweather
Nickname Black Mamba
Weight Junior welterweight
Nationality American
Birth date April 24, 1961 (1961-04-24) (age 46)
Birth place Grand Rapids, MI, USA
Style Orthodox
Boxing record
Total fights 72
Wins 59
Wins by KO 35
Losses 13
Draws 0
No contests 0


Roger Mayweather (born April 24, 1961) is a retired professional boxer. He won two major world titles in two different weight classes. Throughout his career, Mayweather fought against many other boxing champions of the 1980s and 1990s. He is a part of the Mayweather boxing family; his brothers are former welterweight contender Floyd Mayweather Sr. and former IBO super featherweight champion Jeff Mayweather, and his nephew is five-division world champion Floyd Mayweather Jr. Roger eventually became Mayweather Jr.'s trainer.



[edit] Boxing career

[edit] Super featherweight and lightweight
Mayweather who was 64-4 as an amateur made his pro boxing debut on July 29, 1981 against Andrew Ruiz. Mayweather won by TKO in round 1. In his thirteenth fight, Mayweather beat Ruben Muñoz Jr. for the USBA lightweight (135 lb) title. He was known as the Black Mamba for defeating many Mexican opponents.

After improving his record to 14-0, Mayweather earned a titleshot on January 19, 1983 against WBA super featherweight (130 lb) champion Samuel Serrano. Serrano entered the bout with a record of 49-3-1 and had lost only once since first winning the title in 1976. Nonetheless, Mayweather led on all three judges' scorecards before he beat Serrano by TKO in round 8 and effectively ended Serrano's career.
Mayweather made two successful title defenses (against Jorge Alvarado and Benedicto Villablanca), but then his first loss came when he was knocked out in round 1 by Rocky Lockridge on February 22, 1984.

Mayweather won the USBA super featherweight title when he gave Kenny Baysmore his first loss, by TKO in round 3. Thus, Mayweather earned the opportunity to fight against WBC super featherweight champion Julio César Chávez on July 7, 1985. Although Mayweather won the first round on the judges' scorecards, he was knocked down twice in round 2 and lost by TKO.

On November 28, 1986, Mayweather beat Sammy Fuentes for the WBC Continental Americas lightweight title. In his next bout, on March 28, 1987, Mayweather fought against Pernell Whitaker for the NABF lightweight title. Mayweather was knocked down in round 1, but he knocked down Whitaker in round 9. Whitaker won by unanimous decision.

[edit] Super lightweight
After Mayweather moved up to the super lightweight (140 lb) division, he fought against WBC super lightweight champion Rene Arredondo on November 12, 1987. Mayweather led on the scorecards and knocked down Arredondo three times in round 6 to win by TKO.

Mayweather made four successful title defenses before he encountered Julio César Chávez again on May 13, 1989. Chávez was still undefeated at the time, with a 63-0 record. Mayweather retired on his stool because of stomach pain after round 10.

Mayweather won the WBA Americas super lightweight title on April 5, 1990 from Ildemar Paisan. He fought Rafael Pineda for the vacant IBF junior welterweight title on December 7, 1991, but he lost by knockout in round 9.

On March 14, 1993, Mayweather beat former WBA lightweight champion Livingstone Bramble by corner stoppage in round 5. Bramble had defeated Ray 'Boom Boom' Mancini twice for the title in the mid-1980s.

Mayweather defeated Eduardo Montes for the IBO light welterweight title by third-round knockout on May 28, 1994. Less than three weeks later, he defeated Marco Antonio Ramirez by round 3 TKO.


[edit] Welterweight
In his next fight, against Johnny Bizzarro on August 4, 1994, Mayweather won the IBO welterweight (147 lb) title by unanimous decision. He defended the belt once in 1995.

On June 25, 1995, Mayweather fought the 14-0 Kostya Tszyu for the IBF junior welterweight title. Tszyu won by unanimous decision.

Mayweather won his last title—the IBA welterweight title—on March 12, 1997, when he beat Carlos Miranda by round 12 TKO. Mayweather's final bout was a majority decision victory over Javier Francisco Mendez on May 8, 1999. He ended his career with a total of nine major and minor titles in four weight classes.

[edit] Training career
When Floyd Mayweather Jr. turned pro in 1996, Roger Mayweather turned his attention away from his boxing career and focused more on being Mayweather Jr.'s trainer. Roger trained Mayweather Jr. until early 1998, when Floyd Mayweather Sr. was released from prison and became Mayweather Jr.'s trainer. However, soon after Mayweather Jr. defeated Gregorio Vargas on March 18, 2000, Mayweather Jr. fired Mayweather Sr. as his trainer and brought Roger back.

Roger Mayweather garnered national attention during and after Floyd Mayweather Jr. vs. Zab Judah on April 8, 2006. Near the conclusion of the tenth round, Judah hit Mayweather Jr. with a left hand that was clearly below the belt and followed up with a right-handed rabbit punch. After referee Richard Steele called time with five seconds remaining in the round, Roger Mayweather entered the ring and approached Judah but was restrained by Steele. Judah's father and trainer, Yoel Judah, entered the ring and swung at Roger. Zab then went after Roger—taking a swing and grappling with him until security broke it up and cleared the ring. Roger was ejected, but the boxers finished the remaining two rounds, and Mayweather Jr. won by unanimous decision.[1] Five days after the fight, the Nevada State Athletic Commission decided not to overturn the result of the bout, but Roger Mayweather was fined US$200,000 and suspended for one year.[2]
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Not much emphasis is placed on Mayweather's training ability because many people place too much faith in Floyd's overwhelming boxing talents, but I believe we need to consider that Roger is a good trainer who has been in big fights, and who was a champion. He will inevitably pass on such valuable knowledge to fighters who are under his tutelage.

Many people thought Mayweather would have choked on the big stage because of the bright lights but Mayweather came out shinning and went into this fight as relaxed as ever. I attribute this to Roger Mayweather's preparation.

It is interesting that Floyd being the most talented of the two boxers (floyd vs Oscar), Floyd also had the best trainer. In hindsight putting these two factors together, how was it possible (all things being held equal) that Oscar could have won.

Here is the formula

Best Talent + Best Trainer + Best Workout Regiment = Success.

I don't see a boxer between 140-154 eclipsing Mayweahter in any of the above.