TOKYO (Kyodo) -- Nippon Ham Fighters manager Tsuyoshi Shinjo voiced dissatisfaction Monday with posted players switching Japanese clubs upon returning from short spells in Major League Baseball.

Right-hander Naoyuki Uwasawa chose to join Nippon Ham's Pacific League rivals, the SoftBank Hawks, in December, a season after he was posted by the Fighters and signed a minor league deal with the Boston Red Sox. He pitched in two MLB games in 2024.

Uwasawa was the second former Fighters pitcher to make such a move after Kohei Arihara, who was posted after the 2020 season, played in the big leagues for two years with the Texas Rangers before opting to join the Hawks upon his return home.

Shinjo outlined his position during a meeting of the 12 NPB team managers in response to a question from the group's chairman, Lotte Marines skipper Masato Yoshii, another former big leaguer.

"I said I don't want this trend to continue," Shinjo, formerly of the New York Metz and San Francisco Giants, told reporters after the meeting.

Shinjo said players returning to Japan after a year in MLB, as was the case with Uwasawa, should at least spend a year back at the club they left.

"Not making it over there and then choosing to join a different team (to the ones they left in Japan) that makes me think 'What?' as a manager," Shinjo said.