Dodgers’ Roki Sasaki thrives on selective workout regimen (along with Justin Bieber)

PHOENIX – When Dodger strength coach Travis Smith started working with Roki Sasaki early last season, he quickly learned the phenom pitcher had some popularity in the gym.

“He doesn’t like loud music,” Smith recalled with a laugh in a recent interview with The California Post.

So, in an effort to make the young Japanese pitcher feel comfortable in his foreign environment, Smith came up with a new playlist for each training session together.

“I put in some Bounty and Mr. Kids,” Smith said, referring to the Japanese pop groups Shohei Ohtani and Yoshinobu Yamamoto had told him about.

“Also, Justin Bieber,” Smith added with a laugh. “He wanted a little Justin Bieber.”

Over the past year and a half, that has been the soundtrack to Sasaki’s shocking transformation.

A little J-Pop. Little Biebs. And it’s a new kind of training — among Sasaki’s best as an MLB starter — that’s helping the 24-year-old finally thrive again.

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“He’s grown a lot,” manager Dave Roberts said last week, after Sasaki struck out seven batters against the Phillies, finished the rest of May with a 3.18 ERA and most importantly regained 100 mph life on his fastball for the first time all season.

“Even just the eye,” added Roberts, “his body is so much.”

That wasn’t the case when Sasaki signed with the Dodgers, arriving as an international arm talent in need of a better physical foundation.

From an early age, the right-hander was gifted with a triple-digit heater. But last year, the holes in his body became apparent as his velocity slowed while he battled a shoulder injury early in the season.

“He’s a very cooperative person,” Smith said. “But the thing that stopped him was strength.”

So, the team created a program for their new Japanese import, tailoring each individual’s workout plan to match their personalized music playlist.

“When he first came, he showed us, ‘This is my program, this is what I’ve been doing,'” Smith said. “But I think I just gave him what it is you need and gives it to him [was the biggest difference]. Lots of power plans, very cookie-cutter. They are not very specific. So we had the ability to do that. I think that was a big thing.”

The purchase came slowly to the quiet, guarded Sasaki.

Throughout that first spring training, Smith felt doubts about the diminutive 6-foot-2 prospect. He noted that it took some time for Sasaki to start “understanding that he can push the load and it won’t hurt, that it won’t affect him [pitching] technology or something like that.”

In a way, that made Sasaki’s four months on the injured list last year a blessing.

During that time, Smith put him through what was essentially a full-season training program, designing four- to six-week sessions that focused on everything from core strength to shoulder stabilization.

“The biggest thing was consistency, getting him to buy into the system and not change and do it day in and day out,” Smith said. “To make him understand that this is helping his performance, I think that was huge.”

Indeed, the results were evident when Sasaki returned as the club’s season after last season in October. His fastball was good for 100. His confidence in the attacking players was no longer wavering.

Coming into this season, it made Sasaki’s work with the powerhouse seamless.

Although Sasaki is listed at 187 pounds, Smith said he now weighs 205.

“He spent a lot of time with Travis, rebuilding his body and strength,” said team coach Mark Prior. “You can see that some of those things are starting to pay off.”

This year’s allocations, of course, still take time to fully realize.

In the first month of the season, Sasaki struggled with mechanical consistency in his complex delivery, which led to command struggles and a fastball that dropped to 96-97 mph.

Over the past few weeks, however, Sasaki’s installation method has begun to sync back up. It hits the spot again. He installed a new slider and splitter to keep opponents off balance.

Then came last week, when he unleashed a 100 mph four-seamer against Kyle Schwarber in his first at-bat of the game, en route to matching a season-best 98.5 mph with the pitch.

After that, he also said that he was surprised that his speed suddenly increased.

“I made some small changes last week, and there were some advanced parts, so I thought they would go up,” Sasaki said in Japanese. “But I didn’t think it would go up so much all at once.”

That, Dodgers officials believe, is a reflection of the progress Sasaki has made behind the scenes.

Now that his throwing is back where he likes it, it allows his improved strength to increase his possessions.

“He has a foundation now,” Smith said, “and he understands how to use it.”

“He doesn’t need to be looking for speed or chasing speed,” added Roberts. “So you’re in a very good place.”

This isn’t the last goal for Sasaki, who already has a 4.59 ERA this season.

His work with Smith and the group’s fitness staff continues, he keeps a pop music playlist on repeat in the gym.

“You get into him,” Smith said, “and you’re a little more comfortable than before.”