1. Muhammad Ali
   Joe Frazier
2. Ken Norton
   Larry Holmes

At 22 years old, Muhammad Ali won his first world heavyweight championship from Sonny Liston. The pair had a rematch a year later for the same title belt, with Ali again coming out victorious in a first-round knockout. The outspoken Ali refused to be drafted into the Army, citing religious beliefs and his opposition to the war in Vietnam.

1. Roberto Duran
   Wilfred Benitez
2. "Sugar" Ray Leonard
   Leon Spinks

Though he rose to prominence in the 1970s, "Sugar" Ray Leonard helped revolutionize the lower weight classes in the 1980s as one of "The Fabulous Four." His skill in these classes made him one of the best pound for pound fighters of all time.

1. Jerry Quarry
   Joe Frazier
2. George Chuvalo
   Jimmy Young

Known for putting pressure on his opponents, Joe Frazier was a relentless swinger in the ring. This style of fighting was one of the main reasons that 27 of his 32 victories came by knockout.

1. Ken Buchanan
   Roberto Duran
2. Jose Napoles
   Ruben Olivares

Roberto Duran had extreme punching power, earning him the nickname "Hands of Stone." In 119 fights with 103 victories, Duran proved his punching power by winning 70 of those fights by knockout.

1. Carlos Monzon
   Alexis Arguello
2. "Marvelous" Marvin Hagler
   Bob Foster

After becoming the undisputed middleweight champion, "Marvelous" Marvin Hagler defended his title 12 times without a loss. Most of those fights he won by knockout, though he did have a 15 round slugfest against Roberto Duran that ended with a unanimous decision victory for Hagler.

1. Emile Griffith
   Alexis Arguello
2. Eder Jofre
   Jose Napoles

Utilizing an upright stance and a well-placed jab, Alexis Arguello was one of the best defensive boxers of his time. The typical fan probably saw this style as dull, but true boxing experts could appreciate the chess game Arguello could play in the ring.

1. Floyd Patterson
   Charlie Harris
2. Vic Brown
   Terry Daniels

Floyd Patterson might have been past his prime when the '70s rolled around, but he was still a top-level boxer in the early part of the decade. Patterson won nine fights in the '70s and had only one loss during that time before leaving the sport. He also dabbled in acting, his credits including the television series, "Wild Wild West."

1. Roy Williams
   Earnie Shavers
2. Henry Clark
   Oliver Wright

Earnie Shavers never won a world title, but he did have the opportunity to fight twice for championships. His final chance to win a world title came against Larry Holmes. Shavers went toe to toe with Holmes until he was knocked out in the 11th round.

1. Jerry Quarry
   Ken Buchanan
2. Ruben Olivares
   Jimmy Young

Ruben Olivares possessed a deadly left hook that helped send 49 of his first 52 opponents to the ground, with a knockout count as the end result. Olivares won his first title in his 53rd fight, finishing the fight against Takao Sakurai with a knockout in the sixth round.

1. Joe Armour
   Floyd Mayweather Sr.
2. Freddie Jones
   Darryl Penn

After leaving the ring, Floyd Mayweather Sr. trained his son, Floyd Mayweather Jr. The latter surpassed his father in the ring, finishing his career with an undefeated record and holding titles in five weight classes.

1. Earnie Shavers
   Leon Spinks
2. Ken Norton
   Larry Holmes

Larry Holmes, who was mentored by Muhammad Ali, was the only fighter to stop Ali before the final bell rang. The fight took place near the end of Ali's career, a time when Parkinson's disease had already begun to take its toll on Ali.

1. Larry Holmes
   Ken Norton
2. Bob Foster
   George Foreman

George Foreman proved that age is just a number when he defeated Michael Moorer for the unified WBA, IBF and lineal titles at the age of 45. The win made Foreman the oldest world heavyweight champion in history.

1. Carlos Manzon
   Emile Griffith
2. Eder Jofre
   Ruben Olivares

Carlos Monzon had a tough life growing up. As a boy living in Argentina, he was sold to fight. He eventually found his way into professional boxing. After three early losses, Monzon went 81 fights with either a victory or a draw.

1. Boone Kirkman
   Jimmy Young
2. Stan Ward
   Ron Lyle

Ron Lyle didn't have his first professional fight until the age of 30, partly because he spent time in prison during his early life. According to Lyle, one of the prison guards got him interested in the sport during his time behind bars.

1. Al Bell
   Dave Watkins
2. Henry Porter
   James Tillis

James Tiller rose through the boxing ranks in the late '70s, winning 12 straight fights to complete the decade. However, it was in 1986 that he famously fought Mike Tyson to a decision. Though the decision favored Tyson, Tiller was the first fighter to push Tyson to the finish. He says his nickname, the Fighting Cowboy, was given to him by Muhammad Ai.

1. Bob Foster
   Jimmy Young
2. Jerry Quarry
   Ken Norton

Ken Norton received the only world heavyweight title of his career after Leon Spinks forfeited the belt. He lost the title to Larry Holmes not long after gaining it. Holmes defeated Norton by split decision.

1. "Sugar" Ray Seales
   James Redford
2. Vito Antuofermo
   Tracy Morrison

In 1979, Vito Antuofermo defended his middleweight title against "Marvelous" Marvin Hagler. The fight went 15 rounds and ended in a controversial draw, allowing Antuofermo to keep his title belt.

1. Leroy Caldwell
   Lou Bailey
2. Oscar Bonavena
   Santiago Lovell

Oscar Bonavena had one of the toughest fights of his career against Muhammad Ali for the heavyweight title. The match went to the 15th round, where Ali knocked Bonavena down to the mat on three occasions, finishing in a loss for Bonavena.

1. John Tate
   Carlos Ortiz
2. Pierre Fourie
   Hugo Corro

Carlos Ortiz fought from an early age, but it wasn't in the ring. The future International Boxing Hall of Famer grew up on the tough streets of New York City. After learning to fight on the streets, Ortiz transitioned to professional boxing when he turned 18.

1. Wilfred Benitez
   Carlos Zarate Serna
2. Esteban de Jesus
   Ruben Olivares

Turning pro at 15, Wilfred Benitez was the youngest fighter in the history of boxing to win a world title. He was only 17 years old when he won the title by defeating Antonio Cervantes in a match that was decided by split decision.

1. Leon Spinks
   Alan Minter
2. Ronnie Harris
   Jimmy Ellis

Jimmy Ellis had two championship fights in the '70s, both ending in losses. Of course, those fights were also in the stacked heavyweight division against two of the greatest boxers of all time, Joe Frazier and Muhammad Ali.

1. Jimmy Young
   Earl Tripp
2. Michael Dokes
   Ira Martin

An American fighter out of Akron, Ohio, Michael Dokes had a successful amateur career before turning to pros in 1976. One of his best accomplishments as an amateur was winning a silver medal at the 1975 Pan American Games.

1. Carlos Zarate Serna
   Wilfredo Gomez
2. Antonio Cervantes
   Vincente Saldivar

Though small in stature at 5 feet, 5 inches tall, Wilfredo Gomez could throw a punch like no one's business. While at his best in the ring, Gomez won an astounding 32 straight fights by knockout.

1. Teofilo Stevenson
   Jerry Quarry
2. Jose Napoles
   Emile Griffith

Emile Griffith had a professional boxing career that spanned from 1958 until 1977. After he left the sport as a boxer, he turned to training, where he helped boxers like Wilfred Benitez and Juan Laporte win championships.

1. Leon Spinks
   Jimmy Young
2. Jerry Quarry
   Ronnie Harris

After seven victories and one tie, Leon Spinks was given the biggest fight of his career in a heavyweight title match against Muhammad Ali. This took place in 1978. Spinks got the win in what was the only fight Ali lost while holding the title belt.

1. Muhammad Ali
   Joe Frazier
2. Henry Clark
   Duane Bobick

Throughout his career, Duane Bobick had the power to knock opponents out, winning his first 19 professional fights by knockout. Bobick's career began with a 38-0 record before he lost to Ken Norton in 1977.

1. Yum Dong-kyun
   Hong Soo-hwan
2. Yoshida Shuzo
   Tiger Osano

Making his boxing debut in 1970, Yum Dong-kyun had a relatively short boxing career compared to most fighters. He ended his career in 1980 after his bout against Hong Soo-hwan ended in a draw.

1. Esteban de Jesus
   Teofilo Stevenson
2. Carlos Zarate Serna
   Antonio Cervantes

Teofilo Stevenson was known throughout the '70s for his lethal right hand that sent many fighters to the mat. Even when fighters knew about the power his right hand held, they could do little to defend against it, earning Stevenson three gold medals during his prime.

1. Eusebio Pedroza
   Victor Galindez
2. Pierre Fourie
   John Tate

After the WBA light heavyweight title became vacant in 1974, Victor Galindez challenged Len Hutchins for the belt. The fight carried into the 13th round, during which Galindez secured a knockout victory.

1. Jimmy Ellis
   Ken Buchanan
2. George Chuvalo
   Jerry Quarry

Two of George Chuvalo's most famous fights were losses to the great Muhammad Ali. Chuvalo managed to push both matches to the final bell, but the judges ruled in Ali's favor. For his determination, Ali referred to Chuvalo as one of the toughest fighters he has ever faced.

1. Rodrigo Valdez
   Alan Minter
2. Bob Foster
   Ronnie Harris

Though he fought in an orthodox stance, Bob Foster could throw a powerful punch with both hands. He used that power primarily in the light heavyweight division, but occasionally, Foster moved up to the heavyweight division, where the pay was much higher.

1. Vincente Saldivar
   Alan Minter
2. Bruno Arcari
   Pedro Carrasco

After losing the first fight of his career, Bruno Arcari fought 72 more bouts as a professional. Only one of those fights was a loss and another a tie. The rest of the fights went to Arcari.

1. Ismael Laguna
   Jimmy Young
2. Antonio Cervantes
   Arnold Taylor

Throughout his career, Ismael Laguna proved he was one of the best defensive boxers with one of the toughest jaws in the sport. He competed in 75 fights and was never knocked to the mat.

1. Jose Napoles
   Ruben Olivares
2. George Chuvalo
   Jimmy Ellis

Throughout his career, Jose Napoles displayed the ability to beat his opponents to a pulp. In his title fight against Curtis Cokes, Napoles knocked Cokes around so bad that the referee had to stop the fight in the 13th round.

1. Esteban de Jesus
   Jimmy Young
2. Antonio Cervantes
   Vincente Saldivar

Known for his endurance, Vicente Saldivar was a relentless southpaw fighter who enjoyed attacking the body of opposing fighters on the defense. Saldivar's style allowed him to maintain power into later rounds, where he could secure the win with a knockout.

1. Victor Galindez
   Mando Ramos
2. Pedro Carrasco
   Jose Legra

With the ability to avoid hard blows, Jose Legra preserved his body over a long career, during which he fought 150 bouts. The Cuban right-hander had only 12 losses.

1. Rudi Lubbers
   Chuck Wepner
2. Joe Bugner
   Jimmy Young

As with most boxers competing in the heavyweight division in the '70s, Rudi Lubbers had to complete his right of passage by taking a bout against Muhammad Ali. The fight went to Ali, but Rubbers at least went all 12 rounds with the champ.

1. Carlos Zarate Serna
   Eder Jofre
2. Ken Buchanan
   Jerry Quarry

Before starting his professional career, Eder Jofre competed in the Olympics, losing in the quarterfinals of the competition. He wouldn't lose another match until he faced Fighting Harada, who captured Jofre's bantamweight title.

1. Pedro Carrasco
   Carlos Zarate Serna
2. Esteban de Jesus
   Jose Cuevas

After one loss early in his career, Pedro Carrasco won 83 consecutive fights and didn't have another loss until his 92nd fight. He finished his career with 116 wins and only three losses.