De La Cruz scored the tying run on a one-out RBI single by Spencer Steer, and after Jose Trevino singled to load the bases, Benson ripped a single down the right-field line for his third hit of the game to score Gavin Lux and lift the Reds to the victory in the rubber match of the three-game series.
It was the third walk-off win of the year for the Reds and the second of their six-game homestand.
It was just the third blown save of the season for Suarez (2-4), who entered the game as MLB’s save leader with 23.
De La Cruz tied the game in the sixth inning with an RBI single, but San Diego reclaimed the lead in the seventh on Jose Iglesias’ RBI fielder’s choice with the bases loaded.
It was a rare late-inning comeback for the Reds, who came into the game with a 1-34 record when trailing after seven innings.
Cincinnati closer Emilio Pagan (1-2) earned the win after working the ninth inning.
San Diego had been 37-2 when leading after eight.
Xander Bogaerts had a homer and two doubles for the Padres.
Key moment: Trailing 1-0 in the sixth inning, Reds reliever Scott Barlow got Manny Machado to foul out with the bases loaded.
Key stat: The Padres stranded 13 runners and went 0 for 13 with runners in scoring position.