The Seattle Mariners defeated the Chicago Cubs 5–4 on Sunday, with the winning run scoring on a walk-off hit by Randy Arozarena off Cubs reliever Jacob Webb. Webb, who had been performing well this season, surrendered the decisive blow in what multiple outlets described as a significant collapse.
The Cubs had taken the lead in the third inning when Ian Happ crushed a grand slam off the foul pole at T-Mobile Park, giving Chicago an early advantage. The Mariners, however, rallied to secure the victory.
The loss continued struggles for the Cubs, who entered the game looking to end a three-game losing streak. The Mariners, meanwhile, kept climbing the AL wild-card standings with the win.