The Taduran bouts

Following four more fights–two wins, one loss and a draw–he challenged IBF mini-flyweight champion Pedro Taduran on February 27, 2021 at the Bula Gym in General Santos, Philippines.^[5] The bout was initially expected to take place in January, but had to be postponed due to the ongoing COVID-19 pandemic.^[6] In a fight which saw Cuarto box at range while the defending champion took a more aggressive role, Cuarto defeated Taduran over twelve rounds via UD, capturing his first world title with all three judges scoring the bout 115–113.^[7]

Cuatro faced Taduran in an immediate rematch in his first IBF mini flyweight title defense. The bout was initially scheduled to take place at the City Gymnasium in Digos, Philippines on January 29, 2022,^[8] but was eventually postponed for February 6.^[9] Cuatro retained the title by a seventh-round technical decision. The bout was stopped due to a cut on Taduran's forehead, which was caused by an accidental clash of heads in the sixth round, after which Cuatro was awarded the majority decision. Two of the judges scored the fight 65–64 and 66–64 in his favor, while the third judge scored it as an even 65–65 draw. Cuatro knocked Tadruan down in both the second and sixth round and was deducted a point in the third round for an intentional headbutt.^[10]

Cuatro vs. Valladares

Cuatro was expected to make his second IBF mini flyweight title defense against the one-time IBF title challenger Daniel Valladares on May 27, 2022, in Monterrey, Mexico. It was supposed to be his second bout outside of the Philippines and first since September 29, 2017. The bout was later cancelled however, due to undisclosed reasons.^[11] The fight was later rescheduled for July 1, 2022, and took place at the same location and venue.^[12] He lost the fight by split decision. Two judges scored the fight 116–111 and 115–112 in his favor, while the third judge scored the bout 114–113 for Cuatro. Cuatro was deducted a point in the tenth round, for loose glove tape.^[13]