Jack Della Maddalena stunned Belal Muhammad in the main event of UFC 315 to become the new welterweight champion, claiming the title with a unanimous decision in Montreal. Muhammad, who had not lost since January 2019 and was defending his title for the first time, was outperformed by Maddalena, who remains undefeated inside the Octagon. The event also featured Valentina Shevchenko successfully defending her women's flyweight title against Manon Fiorot, with Shevchenko's experience playing a key role in a close fight. Former bantamweight champion José Aldo returned to win his bout against Aiemann Zahabi, hinting at his continued elite striking skills. Alexa Grasso faced Natalia Silva in a competitive women's flyweight fight, with Silva earning a dominant win. Other notable fights included Benoit Saint-Denis defeating Kyle Prepolec. Experts at CBS Sports predicted Maddalena to beat Muhammad, citing Muhammad's recent inactivity and grappling advantages, but the fight was ultimately decided by Maddalena's striking prowess. The event highlighted ongoing storylines such as Jon Jones's uncertain future, legal challenges within the UFC, and injuries affecting upcoming fights, including a toe injury for Merab Dvalishvili before UFC 316.