SAN FRANCISCO — Bryce Eldridge has two dozen major league games under his belt and he’s gotten most of the important firsts out of the way.First plate appearance. First hit. First home run. First standing ovation.Eldridge experienced one more aspect of major league life for the first time Tuesday night. It happened in the fourth inning with a towering drive that left his bat at 105.9 mph and traveled 407 feet. But there was nothing to celebrate. There was no reason to keep the lineup card as a souvenir. The MLB authenticator cannot place a hologram sticker on disenchantment.“I mean, I knew what I was getting into, you know?” said Eldridge, whose ball was caught by Arizona Diamondbacks center fielder Ryan Waldschmidt in the deepest part of Triples Alley. “It’s the first thing people told me when I signed with San Francisco: `You’re gonna get a couple taken there.'”When Eldridge returned to his locker following the Giants’ 7-5 loss and picked up his phone, a message from his agent, Tucker Ward, was waiting for him: Your first time getting Oracled, congratulations.“It’s tough,” Eldridge said. “But there’s nothing you can do about it except keep going, put your head down, keep working.”The Giants envision Eldridge bashing so many drives into the arcade or the cove beyond that the occasional drives their home ballpark contains at the 415-foot mark in right-center field will amount to a flat tax on a high earner. Eldridge hit another pitch that left the bat at 105.9 mph Tuesday night and it resulted in a double. It’s notable that both instances of blistered contact came against a left-hander, Eduardo Rodriguez — the first time Eldridge was in the lineup against a conventional lefty starter this season.Entering the game, he had just five at-bats against lefty pitchers since making his debut last September. His double in the second inning was his first career hit against a southpaw.It marked what might be a turning point in how the Giants decide to develop the 21-year-old hitting prospect while he competes against major league pitching. They want to choose favorable matchups for him. They want to get as many right-handed bats in their lineup as possible against opposing lefties. And since first baseman Rafael Devers never takes a day off, starting Eldridge against a lefty essentially locks down the designated hitter spot and forces them to float Casey Schmitt — who already tied his career high for homers when he belted his 12th of the season Tuesday night — around the diamond.It would be so much easier to sit Eldridge against lefties and hope to use his bat as a threat off the bench.Here’s the problem with that: you don’t treat the organization’s best hitting prospect in at least a decade like he’s a platoon player. Part of Eldridge’s development will be to face lefties. It’s not as if he’s struggled against them in the minor leagues, either.Of course, this problem doesn’t exist once the Giants fully turn over their season to developing for the future. So falling to 0-5 against the Diamondbacks this season, while representing one more step backwards, also might have moved the Giants a step closer to a different path. Nobody is quitting on a season when there are 107 games remaining on the schedule. But the Giants aren’t giving anyone much reason to believe that they are capable of turning this campaign around.