Japan’s Roki Sasaki might be the best pitcher in the world. But when will he arrive in MLB?

It’s a complicated question, but in general, Japan is very protective of its talent. In order to make the move from NPB to MLB, there is a posting system in place.

It works like this, according to Baseball Reference:

For a player to be posted, both the team and player must agree on the posting; usually the player requests to be posted. The team then notifies the NPB Commissioner’s Office that the player will be posted, who then notifies MLB, which in turns notifies all of its teams. The MLB teams used to have four days to submit a “silent” bid for the right to negotiate a contract with the player to the MLB Commissioner’s Office. After the fourth day, the NPB team (via the Commissioner’s Office) was notified of the highest bidder and has four days to accept or reject the bid. If the bid was accepted, the winning MLB team has thirty (30) days to reach an agreement with the player. If the bid was rejected, the player stayed put.

Players often spend nearly a decade in NPB before they’re posted and very few leave Japan before they turn 25. The obvious exception was Ohtani who joined the Los Angeles Angels at 23 years old. But he agreed to an MLB minimum salary and $2.32 million signing bonus to make that happen.

In order for Sasaki to move to MLB, he’d have to ask the Marines to post him. For now, he seems content with playing in Japan.