SAN FRANCISCO -- Wilmer Flores was in pain after fouling a slider from Rangers left-hander Mike Minor off his left shin. He winced as he dropped to the ground, sitting directly atop home plate for a few seconds as he took a moment to regroup.

A salve came four pitches later, when Flores golfed the same type of pitch out to left field for a three-run home run that helped lift the Giants to a 9-2 win in Friday night’s series opener at Oracle Park.

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“I was surprised,” Flores said. “The ball was carrying today, obviously. I didn’t think I got it. But with the ball carrying today, it was a good day just to put the barrel on the ball. Good launch angle.”

Flores and Darin Ruf, two newcomers who were signed this past offseason to give the Giants more right-handed thump against southpaws, drove in three runs apiece as San Francisco improved to 3-0 against left-handed starters this year. The Giants stacked their lineup with right-handed hitters, with Mike Yastrzemski the only lefty bat to start against Minor.

San Francisco entered the fifth inning trailing, 2-1, but a pair of rookies -- Chadwick Tromp and Mauricio Dubón -- ignited a rally with back-to-back singles off Minor. Tromp, who made his second start behind the plate for the Giants, singled through the right side for his first career hit. Manager Gabe Kapler said nearly every player in the dugout immediately signaled for the ball to be retrieved, a sign of Tromp’s popularity in the clubhouse.

The 25-year-old catcher is one of two Major League players from Aruba, along with the Red Sox’s Xander Bogaerts. Tromp spent seven seasons in the Minors and overcame shoulder surgery in 2018, before finally making his big league debut on Wednesday.

“The community back home is going nuts,” Tromp said. “It’s crazy. The whole island is basically celebrating. To be honest with you, I love it. We’re such a small island. This is very important to them, because it puts us on a bigger scale and just shows the world that a small island can also do big things in life.”

Flores soon followed with his second home run of the year, turning a one-run deficit into a 4-2 lead for the Giants.

“When Wilmer was up there, I leaned over to [bench coach] Kai [Correa] and I said, ‘There’s nobody that I’d rather have up in this moment,’” Kapler said. “He came into this season with all of us knowing that he was such a threat against left-handed pitching, so we kind of envisioned this moment way back in the offseason. And then he’s had such success against right-handed pitching as well."

“Obviously, the whole dugout, his teammates and the coaching staff have a ton of confidence in his ability to produce in the big moments. That goes back to our experience watching him as a New York Met when he was kind of the king of clutch.”

The Giants never looked back, adding two runs in the sixth on RBI hits by Tromp and Dubón. They then broke the game open with a three-run seventh, padding their lead with an RBI single by Donovan Solano and a two-run double by Ruf. Solano has 10 RBIs this season, ranking third in MLB behind the the Twins' Nelson Cruz and the Braves’ Dansby Swanson, who each have 11.

“You’ve got to give these guys credit. They are scrappy,” Rangers manager Chris Woodward said. “They may not be household names, but the one thing they do is battle. They don’t give away too many at-bats. There were a lot of tough takes. They put pressure on us."

Rookie right-hander Logan Webb struggled with his command in his second start of the year, yielding two runs (one earned) and walking four over 3 2/3 innings. He was picked up by the Giants’ bullpen, as Conner Menez, Shaun Anderson, Wandy Peralta, Tony Watson and Sam Selman combined for 5 1/3 scoreless innings of relief.

“When Summer Camp started, the work that we put in here at the stadium was very good,” Tromp said. “I built a pretty good rapport with the pitchers. I made them feel that I understood what their strengths are. That’s what we’ve got to do every game. I feel like we did that today.”