On January 21, 1975, a 31-year-old Koichi Wajima (29-3-1, 24 KOs) got a shot at the undisputed super-welterweight championship held by 26-year-old Oscar Albarado (50-6-1, 38 KOs).
Wajima came in to the fight on a 1-fight losing streak with a 72% KO rate, and was fighting after a gap of 7 months and 17 days. Albarado was on a 5-fight win streak with a 66% KO rate, and fighting after a layoff of 3 months and 13 days.
Koichi Wajima defeated Oscar Albarado via unanimous decision in the rematch and wins the WBA, WBC, and The Ring super-welterweight world champion — and becomes the undisputed super-welterweight world champion. Wajima improves his record to 30-3-1, while Albarado adds a loss to his record at 50-7-1.
On May 7, 1972, the 29-year-old undisputed super-welterweight world champion, Koichi Wajima (24-2, 21 KOs), faced a undefined Domenico Tiberia undefined in an undisputed title defense fight.
Wajima came in to the fight on a 11-fight win streak with a 80% KO rate, and was fighting after a gap of 3 months and 5 days.
Koichi Wajima made quick work of Domenico Tiberia, stopping the challenger via KO in the 1st. Wajima improves his record to 25-2 (22 KOs)
On February 17, 1976, Koichi Wajima and Yuh Jae-Doo met again in an immediate rematch.
Wajima came in to the fight on a 1-fight losing streak with a 68% KO rate, and was fighting after a gap of 8 months and 10 days.
In the rematch, Koichi Wajima stopped the champion via KO in the final round of the 15-round world-title fight, and is crowned the new WBA and The Ring super-welterweight champion. Wajima improves his record to 31-4-1 (25 KOs)
On October 3, 1972, the 29-year-old undisputed super-welterweight world champion, Koichi Wajima (25-2, 22 KOs), faced a undefined Matt Donovan undefined in an undisputed title defense fight.
Wajima came in to the fight on a 12-fight win streak with a 81% KO rate, and was fighting after a gap of 4 months and 26 days.
Koichi Wajima made easy work of Matt Donovan, stopping the challenger via KO in the 3rd. Wajima improves his record to 26-2 (23 KOs)
On August 14, 1973, the 30-year-old undisputed super-welterweight world champion, Koichi Wajima (27-2-1, 23 KOs), faced a undefined Silvano Bertini undefined in an undisputed title defense fight.
Wajima came in to the fight on a 1-fight win streak with a 76% KO rate, and was fighting after a gap of 3 months and 26 days.
The challenger refused to continue the fight in the 12th round, and Koichi Wajima is crowned the new super-welterweight world champion. Wajima improves his record to 28-2-1 (24 KOs)
On October 31, 1971, a 28-year-old Koichi Wajima (22-2, 20 KOs) got a shot at the WBA welterweight title held by Carmelo Bossi.
Wajima came in to the fight on a 9-fight win streak with a 83% KO rate, and was fighting after a gap of 5 months and 3 days.
Koichi Wajima defeated Carmelo Bossi via split decision and wins the WBA title — in his first world-title fight. Wajima improves his record to 23-2
On February 5, 1974, the 30-year-old undisputed super-welterweight world champion, Koichi Wajima (28-2-1, 24 KOs), faced a undefined Miguel De Oliveira undefined in an undisputed title defense fight.
Wajima came in to the fight on a 2-fight win streak with a 77% KO rate, and was fighting after a gap of 5 months and 22 days.
Koichi Wajima defeated Miguel De Oliveira via majority decision in the rematch and successfully defended his WBA and WBC super-welterweight titles. Wajima improves his record to 29-2-1
On April 19, 1973, the 29-year-old undisputed super-welterweight world champion, Koichi Wajima (26-2-1, 23 KOs), faced a undefined Ryu Sorimachi undefined in an undisputed title defense fight.
Wajima came in to the fight after a draw in his last fight with a 79% KO rate, and was fighting after a gap of 3 months and 10 days.
Koichi Wajima defeated Ryu Sorimachi via majority decision and successfully defended his WBA and WBC super-welterweight titles. Wajima improves his record to 27-2-1
On January 9, 1973, the 29-year-old undisputed super-welterweight world champion, Koichi Wajima (26-2, 23 KOs), faced a undefined Miguel De Oliveira undefined in an undisputed title defense fight.
Wajima came in to the fight on a 13-fight win streak with a 82% KO rate, and was fighting after a gap of 3 months and 6 days.
The fight ended in a majority decision draw and both the fighters added a draw to their respective records — Wajima is now 26-2-1.
On May 28, 1971, a 28-year-old Koichi Wajima (21-2, 19 KOs) and Tetsuo Hoshino met in the ring for the 2nd time, in a super-welterweight bout.
Wajima came in to the fight on a 8-fight win streak with a 82% KO rate, and was fighting after a gap of 2 months and 2 days.
In the rematch, Koichi Wajima stopped Tetsuo Hoshino via KO in the 2nd round. Wajima improves his record to 22-2 (20 KOs)