Kiermaier also made a rocket throw from center field to cut down Cody Bellinger at home plate, keeping the score tied 1-all in the sixth. Bellinger, who was aboard on a fielder's choice, failed to reach base safely for the first time in 46 starts this season. He went 0 for 4, dropping his major league-leading batting average to .394.
Garcia's eighth homer came off Dylan Floro, who entered with a 0.44 ERA - best among NL relievers. Floro (1-1) pitched to four batters and got none of them out.
Kiermaier capped the big inning with his fourth home run, which came off left-hander Caleb Ferguson.
Pham led off the fourth with his sixth homer, an opposite-field shot off starter Rich Hill.
Tampa Bay opener Ryne Stanek pitched 1 2/3 innings, giving up a hit and a walk while striking out two.
After Muncy's home run in the sixth, Bellinger kept the inning going by beating a throw to first base to prevent a double play. He tried to score the lead run on Russell Martin's two-out single, but Kiermaier threw him out.
Bellinger's 45-game on-base streak to start the season stands as the sixth-longest in major league history. The longest, 57 games, was accomplished by John Olerud of the New York Mets in 1999.
Dodgers: RHP Pedro Baez will be available to pitch Friday after being hit by a line drive just below the right knee Tuesday night. ... RHP Kenta Maeda (left adductor strain) will pitch Sunday at Pittsburgh, his first start since May 15.
Rays: 3B-1B Yandy Diaz, hit on the left hand by a pitch Sunday, was out of the lineup for the second straight game. ... INF Joey Wendle, out since April 26 with a broken right wrist, had his cast removed and will increase range of motion and strengthening drills. ... Rehabbing INF Matt Duffy aggravated his strained left hamstring and will be evaluated.
Dodgers: RHP Walker Buehler (4-1, 3.83 ERA) will pitch Friday night's opener of a three-game series at Pittsburgh.
Rays: A four-game series starts Thursday night at Cleveland, where the Rays are 27-51 all-time.
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