The rookie Puig, trying to bust his way into an outfield filled with All-Stars, also singled twice and tripled, and stole a base. He's batting .489 with a team-high 10 RBIs. His monster two-run homer in the first inning was immediately followed by Jerry Hairston's solo shot off Oakland starter Dan Straily.
Capuano held the A's scoreless until Cespedes lined his homer over the wall in left-center leading off the fifth inning.
Puig, the $42 million signing last summer, didn't hustle out of the batter's box on his fifth-inning single and was thrown out at second trying to stretch by Cespedes, who initially misplayed the shallow fly, but Puig made up for it by legging out a triple to lead off the bottom of the seventh. Had Puig recorded the double in the fifth, he would have hit for the cycle.
The Dodgers added to their lead in the fifth inning off reliever Jordan Norberto, with Nick Punto's infield single plating a run that was unearned because of shortstop Hiroyuki Nakajima's fielding error.
Capuano, on the bubble to stay in the rotation with a pre-game ERA of 10.61, was removed after 5 2/3 innings having allowed five hits and one walk, with four strikeouts.
Mark Lowe inherited two runners from Capuano and retired Cespedes on a popout to end the sixth inning.
Up next: Aaron Harang, still trying to fight his way back into the rotation, gets the ball on Wednesday with the scratch of the injured Chad Billingsley. Harang will be facing the Royals and Wade Davis on the road. Matt Kemp, Adrian Gonzalez and Luis Cruz, who did not play on Tuesday, are expected to return to the lineup.
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.