Japanese ace Roki Sasaki will be available to Major League Baseball teams this offseason.

The Chiba Lotte Marines announced Saturday they have chosen to start the process of moving the pitcher to a big league club in North America via the posting system.

The right-hander, who turned 23 this month, is expected to become one of the most sought-after pitchers on the open market. He went 10-5 with a 2.35 ERA in 18 games this year, striking out 129 hitters in 111 innings.

Because he is younger than 25, Sasaki will be classified as an international amateur free agent subject to international bonus pool limits, according to MLB rules. That means his first contract would be a minor league deal no larger than seven figures.

The Marines will receive a percentage fee for posting him, with the amount determined by the size of his contract.

It’s unclear yet when Sasaki will officially be posted, starting the 45-day clock for him to sign with a major league club.

Sasaki helped Japan win the 2023 World Baseball Classic. His fastball has been clocked at 102.5 mph, and he had a 29-15 career record with a 2.10 ERA over four injury-shortened seasons with the Marines. He pitched a perfect game against the Orix Buffaloes in April 2022.

“Since I joined the team, the team has been listening to my thoughts about my future MLB challenge, and I am very grateful to the team for officially allowing me to post,” Sasaki said in a statement posted by the Marines on X, the social media site formerly known as Twitter.

“There were many things that did not go well during my five years with the Marines, but I was able to get to this point by concentrating only on baseball, with the support of my teammates, staff, front office, and fans. I will do my best to work my way up from my minor contract to become the best player in the world, so that I will have no regrets in my one and only baseball career and live up to the expectations of everyone who has supported me this time.”