Peralta (3-5) allowed seven hits and walked two -- both with the bases loaded -- in a 1 2/3-inning outing in which he was charged with six runs (four earned).
Nick Punto, Juan Uribe and Ramon Hernandez all singled to load the bases with none out. After a strikeout, Crawford singled in two runs. Mark Ellis singled, again loading the bases. Adrian Gonzalez reached on an error by shortstop Jean Segura that made the score 4-0.
After Kemp struck out, Scott Van Slyke and Punto each walked, forcing in runs and Peralta out of the game.
Hernandez connected for his first home run of the year in the third.
Ryu Hyun-Jin (5-2) cruised to the win, giving up six hits over 7 1/3 innings and single runs in the sixth and eighth innings. Ryan Braun has a home run for the first Brewers run and Jonathan Lucroy knocked in the other.
Van Slyke doubled in a run and scored another for Los Angeles in the ninth.