MIAMI -- Maybe there is some untapped firepower in the Marlins’ lineup after all.

Jorge Alfaro and Garrett Cooper each showed some serious pop on Tuesday night, both connecting on three-run home runs in Miami’s 11-3 blowout of the Giants in the series opener at Marlins Park.

Winners for the eighth time in the last 11 games, the Marlins had a rare victory with their big damage coming via the home run. In fact, the club hadn’t had a three-run home run all season before Alfaro blistered his no-doubt blast to center off Nick Vincent in a four-run fifth inning. And in the eighth inning, Rosell Herrera clobbered a pinch-hit, solo home run.

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The Marlins used a 14-hit attack, with four extra-base hits -- Starlin Castro had a two-run double in the third inning.

“It just continues to build when you have guys on base,” Marlins manager Don Mattingly said. “You're not hitting three-run homers if you don't have guys on base.”

Statcast projected Alfaro's drive at 438 feet, with an exit velocity of 111.7 mph. Breaking the game wide open was Cooper’s blast to left-center off Derek Holland in the sixth inning. The drive into AutoNation Alley was tracked at an estimated 414 feet with a 103.7 mph exit speed. Herrera’s HR was 403 feet, 103.9 mph.

“I just try to put the ball in play,” Alfaro said. “Get a good pitch, and try to get on base for my teammates. Try to help my teammates however I can.”

For Alfaro, making contact has been a struggle. He has a 35.3 strikeout percentage, but when he puts the bat on the ball, he’s capable of doing damage. He entered the game with a 44.3 hard-hit percentage.

Miami’s season-high 11 runs gave plenty of support to Trevor Richards, who gave up one run on two hits in seven innings. Ironically, Richards’ first pitch of the night was knocked over the wall in right for a homer by Joe Panik. The only other hit Richards yielded was a one-out single to Brandon Crawford in the fifth.

“You can’t get off to a better start,” Giants manager Bruce Bochy said. “Leadoff hitter hits the first pitch out of the ballpark, and you think the momentum was going to swing over, and we'll get these bats going. It was just the opposite. Their guy pitched good. Used his changeup effectively, spotted his fastball. Wasn't a lot of hard contact.”

The Marlins are last in the Majors in home runs with 39. Even when they’ve connected, they haven’t done considerable damage, because 27 are solo shots.

“We are going to go out and compete every pitch,” Alfaro said. “We're going to go out and battle every at-bat. That's how it's going to be. I think everybody is seeing that, not just from me, but from everybody. We're going out there to compete.”

Since May 17, when the Marlins started their 8-3 stretch, they’re hitting .268/.325/.437 as a team, with 15 home runs and 19 doubles.

“It's what we internally had all felt, that our offense was not as bad as it was performing,” Marlins president of baseball operations Michael Hill said before the game.