On April 23, 2016, a 30-year-old McWilliams Arroyo (16-2, 14 KOs) got a shot at the flyweight WBC and The Ring title held by 28-year-old Nicaraguan boxer Román González (44-0, 38 KOs).
Arroyo came in to the fight on a 1-fight win streak with a 77% KO rate, and was fighting after a gap of 1 year and 12 days. González was on a 44-fight win streak with a 86% KO rate, and fighting after a layoff of 6 months and 6 days.
Román González defeated McWilliams Arroyo via unanimous decision and successfully defended his WBC and The Ring flyweight titles. González improves his record to 45-0, while Arroyo adds a loss to his record at 16-3.
On February 27, 2021, a 35-year-old McWilliams Arroyo (20-4, 15 KOs) and Abraham Rodriguez met in the ring in a flyweight bout.
Arroyo came in to the fight on a 3-fight win streak with a 62% KO rate, and was fighting after a gap of 1 year, 2 months, and 20 days.
McWilliams Arroyo stopped Abraham Rodriguez via TKO in the 5th round. Arroyo improves his record to 21-4 (16 KOs)
On February 24, 2018, a 32-year-old McWilliams Arroyo (16-3, 14 KOs) and a 29-year-old Mexican boxer Carlos Cuadras (36-2-1, 27 KOs) met in the ring in a super-flyweight bout.
Arroyo came in to the fight on a 1-fight losing streak with a 73% KO rate, and was fighting after a gap of 1 year, 10 months, and 1 day. Cuadras was on a -1-fight win streak with a 69% KO rate, and fighting after a layoff of 5 months and 15 days.
McWilliams Arroyo defeated Carlos Cuadras via majority decision in the 10-round super-flyweight fight. Arroyo improves his record to 17-3, while Cuadras adds a loss to his record at 36-3-1.
On June 19, 2014, a 28-year-old McWilliams Arroyo (14-1, 12 KOs) and a 25-year-old Filipino boxer Froilan Saludar (19-0-1, 12 KOs) met in the ring.
Arroyo came in to the fight on a 11-fight win streak with a 80% KO rate, and was fighting after a gap of 1 year, 4 months, and 17 days. Saludar was on a 13-fight win streak with a 60% KO rate, and fighting after a layoff of 2 months and 7 days.
McWilliams Arroyo stopped Froilan Saludar via TKO in the 2nd round. Arroyo improves his record to 15-1 (13 KOs), while Saludar adds a loss to his record at 19-1-1.
On September 8, 2018, a 32-year-old McWilliams Arroyo (17-3, 14 KOs) and a 29-year-old Japanese boxer Kazuto Ioka (22-1, 13 KOs) met in the ring in a super-flyweight bout.
Arroyo came in to the fight on a 1-fight win streak with a 70% KO rate, and was fighting after a gap of 6 months and 15 days. Ioka was on a 8-fight win streak with a 56% KO rate, and fighting after a layoff of 1 year, 4 months, and 16 days.
Kazuto Ioka defeated McWilliams Arroyo via unanimous decision in the 10-round super-flyweight fight. Ioka improves his record to 23-1, while Arroyo adds a loss to his record at 17-4.
On June 15, 2019, a 33-year-old McWilliams Arroyo (18-4, 14 KOs) and Carlos Buitrago met in the ring in a flyweight bout.
Arroyo came in to the fight on a 1-fight win streak with a 63% KO rate, and was fighting after a gap of 3 months and 30 days.
McWilliams Arroyo defeated Carlos Buitrago via unanimous decision in the 10-round flyweight fight. Arroyo improves his record to 19-4
On September 10, 2014, a 28-year-old McWilliams Arroyo (15-1, 13 KOs) got a shot at the flyweight IBF title held by 34-year-old Thai boxer Amnat Ruenroeng (13-0, 5 KOs).
Arroyo came in to the fight on a 12-fight win streak with a 81% KO rate, and was fighting after a gap of 2 months and 22 days. Ruenroeng was on a 13-fight win streak with a 38% KO rate, and fighting after a layoff of 4 months and 3 days.
Amnat Ruenroeng defeated McWilliams Arroyo via split decision and successfully defended his IBF flyweight title. Ruenroeng improves his record to 14-0, while Arroyo adds a loss to his record at 15-2.
On February 5, 2011, a 25-year-old McWilliams Arroyo (5-1, 4 KOs) and Manuel Galaviz met in the ring.
Arroyo came in to the fight on a 2-fight win streak with a 66% KO rate, and was fighting after a gap of 2 months and 30 days.
McWilliams Arroyo stopped Manuel Galaviz via TKO in the 1st round. Arroyo improves his record to 6-1 (5 KOs)
On November 6, 2010, a 24-year-old McWilliams Arroyo (4-1, 3 KOs) and Cesar Grajeda met in the ring.
Arroyo came in to the fight on a 1-fight win streak with a 60% KO rate, and was fighting after a gap of 2 months and 9 days.
McWilliams Arroyo stopped Cesar Grajeda via TKO in the 1st round. Arroyo improves his record to 5-1 (4 KOs)
On July 1, 2011, a 25-year-old McWilliams Arroyo (8-1, 7 KOs) and Lorenzo Trejo met in the ring.
Arroyo came in to the fight on a 5-fight win streak with a 77% KO rate, and was fighting after a gap of 1 month and 25 days.
McWilliams Arroyo stopped Lorenzo Trejo via TKO in the 2nd round. Arroyo improves his record to 9-1 (8 KOs)