SAN FRANCISCO — Dominic Smith could only laugh at what he was seeing.

It was May 2024, and Smith had just signed with the Boston Red Sox when he met with hitting coach Peter Fatse to review film. Fatse didn’t believe Smith was maximizing his athleticism in the batter’s box, so he combed through Smith’s old footage to find examples of Smith doing so.

Fatse didn’t show Smith videos from 2020, the year that Smith earned MVP votes. They didn’t watch footage from Smith’s early years with the New York Mets or his time in the minor leagues either. Fatse went way back. For the first time in a decade, Smith sat down and watched a video of himself as a senior at Gardena’s Junipero Serra High School.

“When he pulled up that video, it was a skinny, 175-pound kid with a high leg kick with my hands super low,” said Smith, who has a career .716 OPS over nine seasons. “I didn’t think he was serious. He literally looked me in my eye and said, ‘Bro, this is you.’ It just clicked from there.”

“I was looking at Dom and I said, ‘I don’t think you’re using your athleticism to your advantage. Here’s an extreme example of how you hit when you were a kid, walk me through the progression of how you go there now,’” Fatse said.

Smith, who joined the Giants last week on a major-league deal amidst Buster Posey’s roster shakeup, experienced plenty of life between being a high school senior in California and a major-league veteran in Boston.

The New York Mets selected Smith with the 11th overall pick in the 2013 MLB draft, and he gradually climbed through the Mets’ system, making his debut in 2017.

Smith, now 29, oscillated between the majors and minors over his first two seasons but entered spring training in 2019 with an opportunity to seize the starting job. Pete Alonso snatched that title by hitting 53 home runs, the most ever by a rookie.

The Mets subsequently moved Smith to left field, and while had his stretches of productivity — namely when he finished 13th in NL MVP voting during the COVID-shortened 2020 season — injuries and inconsistency defined the back half of his tenure. Following the 2023 season, Smith became a free agent.

Somewhere along the way, Smith deviated from what he did well. The laundry list of voices in his ear didn’t help. In New York, Smith played under four different managers and had five different hitting coaches. Smith wanted to appease everyone; his development stunted as a result.

“A lot of times, it’s getting you away from what you do well. It took a long time for me to really understand and learn and grow and figure things out,” Smith said. “I talk about never being satisfied, never pointing the finger out — I always point the finger in on myself and look at me and what I can do better,” Smith said.

In Boston, with the help of a couple YouTube videos from 2012, Fatse would help get Smith back to what he was doing well.

Prior to working with Fatse, Smith had never thought to review his mechanics as a teenager. Smith didn’t think there was a correlation between high school-level mechanics versus MLB-level mechanics. As they dove in, Fatse pointed out that Smith generates most of his power with his hands, something Smith considers an “old-school approach.”

Smith said that over time, he moved his hands up high and began worrying about his posture, which restricted what he did well. To Smith, some hitters are more rotational and some are more linear. Smith assessed that he was very linear in high school but he was trying to become rotational.

“He asked me why I stopped doing some of the things I did when I was in high school. To be honest, I didn’t know why,” Smith said. “A lot of it was chasing something that I wasn’t, trying to make it look a certain way — thinking if it didn’t look this way, then it wouldn’t work — instead of just being myself.”

The Giants represent Smith’s fifth organization in three years after a stint this season with the Yankees’ Triple-A affiliate, and he hasn’t needed much time to endear himself to his new team.

In his second game as a Giant, he drove in the go-ahead run with a two-run double. He’s made several excellent defensive plays as well, including Friday night when he reached over the railing in foul territory and fell into the netting to record an out.

“He’s Dom Smooth, man,” Fatse laughed. “The boys called him D-Smooth. He’s always got a smile on. He comes to the cage. He has a very nice, calm, easy presence. He likes to be with the guys. … His teammates loved him. Everybody in the clubhouse enjoyed our time with him.”

Smith believes believes he’s learned a lot over his nine-year major-league career but added that “the job is never finished.” He considers perseverance is one of his defining traits, a glass-half-full mindset due in part to his faith. With top prospect Bryce Eldridge not yet ready for the majors, Smith figures to hold down the Giants’ first base spot for the foreseeable future.

“He’s a guy that has shown over the course of his career that puts together good at-bats,” Posey said. “He’s going to hit for some power. I know that’s not the key component of his game, but hopefully he has quality at-bats. We’re a team that has to keep the line moving. We have to do the small things right. We have to hit behind runners at certain times and able to execute the fundamentals of the game. We believe he’s a guy that can do that.”