SAN FRANCISCO -- Two hours before making his Giants debut, Kris Bryant sat in the home dugout at Oracle Park and was asked if he thought the pressure was on after watching two of his former Cubs teammates, Anthony Rizzo and Javier Báez, homer in their first games for the Yankees and Mets, respectively.

“It’s been cool to see what they’ve done in their debuts,” Bryant said. “Maybe there’s some magic here.”

Bryant soon joined his friends in making an immediate impact for his new club, blasting a solo home run to left field in his second at-bat to help the Giants clinch a series victory with a 5-3 win over the Astros on Sunday afternoon.

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Bryant, Báez and Rizzo became the first trio in the Modern Era to each homer in their debut with a new team after playing on the same club earlier that season, according to STATS.

“We were saying that his other teammates that got traded all homered in their first games as well, so we were going to send him back if he didn’t homer himself,” Darin Ruf said. “Luckily, we get to keep him.”

Ruf added a two-run shot in the fifth as part of a three-hit, three-RBI day, and right-hander Logan Webb fired six-plus innings of two-run ball as the Giants took two of three from the Astros in an Interleague matchup between the teams with the best records in their respective leagues. San Francisco improved to 66-39, the best mark in the Majors, to stay three games ahead of the Dodgers in the National League West.

“I think it says that we’re steady and we’re not going to let one day spill into the next,” manager Gabe Kapler said. “But I also think that the confidence is growing. I think we’ve played very well against some of the best teams in baseball.”

The Giants established themselves as legitimate contenders before trading for Bryant, but they’re looking even more fearsome after adding the 2016 NL MVP and four-time All-Star to their deep lineup.

“I’ve had an unbelievable first day,” Bryant said. “It’s blown my expectations.”

Bryant’s arrival created a palpable buzz around the ballpark, with the 29,655 fans in attendance greeting the 29-year-old slugger with a rousing standing ovation when he stepped up for his first at-bat against Astros right-hander Luis Garcia in the first inning.

Bryant, who batted second and started at third base after being acquired for prospects Alexander Canario and Caleb Kilian on Friday, struck out on eight pitches, but he sent the crowd into a frenzy two innings later when he smashed his 19th home run of the year and his first for San Francisco.

Bryant hammered an 0-1 fastball from Garcia out to left to put the Giants on the board and spark a three-run rally that turned a two-run deficit into a 3-2 lead in the third inning. He became the 50th Giants player since at least 1901 to homer in his Giants debut and the first since Alex Dickerson on June 21, 2019, at Arizona.

“I’ve had some really special fan moments in my career that do give me the goosebumps, and that ranks up there pretty high,” Bryant said of the way the fans welcomed him to Oracle Park.

Bryant’s solo shot kicked off a two-out rally against Garcia, who then surrendered a double into the right-field gap to Mike Yastrzemski and a walk to Buster Posey. Brandon Crawford and Ruf followed with back-to-back singles to give the Giants a lead they wouldn’t relinquish.

The good first impressions cut both ways, as Bryant raved about the steps the Giants took to make him feel welcome in his new organization over the last two days. When he walked into his hotel room in San Francisco on Saturday, Bryant found a bunch of Giants gear, including a set of his No. 23 jerseys laying on the bed for him and his wife, Jessica, and their young son, Kyler.

“When you talk about making a first impression on me and my wife, it was a pretty good one,” Bryant said. “Kyler would not let go of the jersey last night. He’s recognizing the Giants logo now and he keeps saying ‘Daddy,’ to that logo, so it’s really special. I’m over the moon right now.”