SAN FRANCISCO — Few teams have been able to crack Giants starter Robbie Ray.

In his first full season back from 2023 Tommy John reconstructive elbow surgery, Ray had pitched to a 2.93 ERA in 159 2/3 innings before Friday night and made his first trip to the All-Star Game since 2017.

Yet the Orioles had no issue getting to him, as Ray gave up a season-high six runs. Ryan Mountcastle had four RBIs, his most in over a year, and three hits, and Emmanuel Rivera, in his second game back from Triple-A Norfolk, was responsible for two runs.

Seems like a recipe for a win, right?

Wrong.

See, after the offense gave Baltimore an early 1-0 lead, Dean Kremer quickly dug the Orioles into a hole that they couldn’t get out of as the Giants took Game 1 of the three-game series 15-8.

It started badly. Then it only got worse. Kremer walked two of the first three batters he saw, then the scoring spree started. An RBI single for Matt Chapman, a sacrifice fly from Dominic Smith, a two-run single from Luis Matos.

“Some days they find the fielders, and some days they don’t,” Kremer said. “Today was not one of those days where they find the fielders and we got beat through the six hole quite a few times and the four hole a few times, and it kind of kept happening.”

By the time the first inning ended, the Giants were up 4-1 and Kremer had thrown 39 pitches, a troubling sign for a bullpen that was decimated by the trade deadline and has cost the team multiple games this season, including one two days ago against the Red Sox.

One bad inning isn’t uncommon for Kremer, who has a tendency to let one frame balloon on him before reining it back in. Just this time that wasn’t the case. The Giants scored two more runs in the second, then one in the third.

Kremer was pulled after 76 pitches in three innings, his shortest start since June 30, 2023. The seven earned runs he allowed were a season high and tied his career high.

His hot-and-cold tendencies have become the story of his season.

Some nights, he’s stellar. He’s had seven starts in which he’s pitched into at least the seventh inning, three of which were scoreless outings. But he also has nine starts when he’s allowed over five runs, the team losing all but one of those games.

His redeeming quality has been his durability — he hasn’t missed a start, pitching a team-high 155 1/3 innings — but he comes with extreme variability. His goal for the rest of the season is to finish with an ERA under 4.00, something he’s done only once, in 2022, when he made only 21 starts. He is sitting at 4.53 after Friday’s start, with just a month of the season left.

“He’s just got to kind of floor it from the get-go, for me,” interim manager Tony Mansolino said. “I think, when Kremer is good, he floors it, he presses down on the gas pedal right away, and he goes and he attacks. I think when Kremer gets in trouble he feels for things a little bit and tries to find the solutions instead of maybe force the solutions a little bit.”

If things were bad with Kremer, they only got worse when the bullpen took over. Corbin Martin filled two necessary innings for the Orioles, allowing three runs. Yennier Cano, who has struggled for most of the season, made it through his 1 1/3 innings unscathed.

And, if things didn’t already look bleak for the Orioles, the seventh inning was another kick while they were down. Grant Wolfram took over for Cano with one out and the Giants up 10-6. Then the avalanche began.

The Orioles made three errors — a fielding miscue from Jackson Holliday and throwing errors from Dylan Beavers and Rivera — leading to four runs. With the game so far out of reach, the Orioles kept Wolfram in for the eighth and he allowed another run.

“That seventh inning was ugly, without a doubt,” Mansolino said. “We’ve seen our guys do that this year where games get out of hand and we don’t help ourselves in a lot of ways, and that happened right there.”

This article has been updated.