Starting pitcher Adrian Houser didn’t pitch as well in the second half of the season after being traded to the Tampa Bay Rays, posting a 4.79 ERA in 10 starts. (Chris O’Meara/AP)

Adrian Houser, the San Francisco Giants’ newest starter, said that Buster Posey and the rest of the front office were “adamant and pretty consistent” about signing him throughout the offseason.

Much of that, Giants GM Zach Minasian said last week, was the result of some mechanical changes Houser made. On a video call with reporters Monday, Houser went more in depth into the tweaks that added 2 mph to his fastball.

Back home in Oklahoma last winter, Houser discovered the issues while working out at a training facility felicitously named Pitching Works. He was incorporating his quads too much into his delivery when he should have been using his hamstrings and glutes, and the fix was pretty simple.

“They kind of noticed right away at the beginning of the offseason that I wasn’t really getting into my back side very well, my front leg was kind of low,” he said. “I wasn’t really raising it up to where it needed to be.

I also got my hands away from my body a little bit to kind of let them work a little bit more freely and, as we pieced that together throughout the offseason, everything was coming out really well. I just felt freed up and everything was coming out a lot easier.”

He made two starts with the Rangers last spring, putting up a 3.77 ERA and allowing opponents a .216 average with his higher velocity and crisper breaking pitches, but he didn’t make the roster and went to Triple-A Round Rock instead.

His numbers there were indifferent, but the Pacific Coast League is a hitters’ league and skews pitchers’ numbers. When Houser opted out of his Rangers deal on May 15, the White Sox came calling. He flourished with Chicago, with a 2.10 ERA in 11 starts.

The White Sox dealt Houser to the Rays at the deadline, and he slipped to a 4.79 ERA, some of it because Tampa Bay was playing at Triple-A Steinbrenner Field. Houser allowed opponents just a .217 average there, but his ERA was 5.12. Plus, the Rays had just traded their primary catcher,

Danny Jansen, to the Brewers, and Houser’s catchers were Hunter Feduccia, acquired the same day from the Dodgers, and Nick Fortes, picked up two days earlier from Miami. Houser had a 5.76 ERA in five starts working with Feduccia.

“It was kind of a big adjustment period for everybody,” Houser said. “And then the ballpark there in Tampa didn’t play too well for anybody, really, but you know, that’s just part of the game.

I think it was just a few things here and there, but overall, I felt like I was doing the same thing and felt really good through the end of the season.”

His slider improved in Tampa Bay after a grip shift, Houser said, helping him get a few more outs against lefties. The slider velocity was up a tick or two in his final three starts – averaging 90.5 mph in one game – and he threw it more than 28% of the time those outings.

That’s something he can build off next season; for a sinkerballer, an effective slider is an excellent weapon, particularly the second time through the order.

“We noticed it was working better and just rolled with that,” Houser said.

In San Francisco, Houser, 32, will have every sinkerballer’s dream, a terrific infield defense, especially on the left side with Gold Glove third baseman Matt Chapman and shortstop Willy Adames.

Casey Schmitt is still learning second but is known for his glove, and Rafael Devers is learning first but showed promise. Noted infield coach Ron Washington is joining the staff, too, and catcher Patrick Bailey has won back-to-back Gold Gloves.

“I’m excited to get back with Willy,” said Houser, who played with Adames for 2½ seasons in Milwaukee. “The guy comes ready every day, and you know he wants to win and he shares that passion with everybody.

I’m absolutely excited to get with those guys behind me, hopefully getting them a lot of ground balls. I’m excited to work with Patrick – it’s going to be a fun, exciting year, for sure.”

Houser, who signed a two-year, $22 million deal last week, is expected to slot into the fourth or fifth slot in the rotation. The Giants hold a club option for 2028.