Red Sox to acquire righty Naoyuki Uwasawa from the Rays

The Red Sox are acquired right-hander Naoyuki Uwasawa from the Rays, per Jeff Passan of ESPN. Marc Topkin of The Tampa Bay Times had relayed earlier that the righty triggered an assignment clause and the Rays were close to making a trade. The Rays will receive cash considerations, per Topkin.

Uwasawa, 30, has a long track record of success in Japan’s Nippon Professional Baseball but inked a minor league pact with the Rays over the winter. He most recently tossed 170 innings with a 2.96 ERA in NPB, though that strong mark was accompanied by a lackluster 17.8% strikeout rate and sub-par velocity. 

Last September, MLBTR contributor Dai Takegami Podziewski noted that Uwasawa’s fastball velocity was averaging 90.8 mph during the 2023 NPB season. Uwasawa does boast a strong 7.5% walk rate, which dropped as low as 5.9% in 2023, but he’s generally viewed as a soft-tossing finesse pitcher.

It’s been a tough spring for Uwasawa, though the bulk of the damage against him came in his debut effort with the Rays. The Braves tattooed the right-hander for seven runs on eight hits in just two innings of work. 

Uwasawa has had two sharp outings (one against the Red Sox) and another rough one (also against Boston) in the weeks since that time. His spring ERA sits at a dismal 13.03, owing largely to that first meltdown of an outing.

For a Red Sox club in need of rotation depth, however, there’s little harm in adding Uwasawa to the fold — particularly since he’ll only cost them cash considerations. In parts of nine NPB seasons, Uwasawa has amassed 1118 1/3 innings of 3.19 ERA ball with a 19.7% strikeout rate and 7.5% walk rate. 

He’s been particularly effective in recent years, compiling a 3.08 ERA over his past six NPB seasons. He made the NPB All-Star team in both 2021 and 2023. Uwasawa also tossed two shutouts and averaged better than seven innings per start during the 2023 season.

The Red Sox will open the season with a rotation including Brayan Bello, Nick Pivetta, Tanner Houck, Garrett Whitlock and Kutter Crawford. They recently signed veteran righty Chase Anderson to a big league deal, giving them some additional depth, though he could begin the season as a long man in the bullpen. 

There’s plenty of talent in the group but also some injury risk and plenty of short MLB track records. Boston tried to address some of its rotation deficiency this offseason by signing Lucas Giolito to a two-year contract, but he suffered a UCL tear earlier this spring and will miss the entire 2024 season after undergoing an internal brace procedure. Depth starter Chris Murphy, too, will miss the season due to his own UCL surgery.

Uwasawa will join a group of depth options including not only Anderson but also lefty Brandon Walter and righty Cooper Criswell. 

The Red Sox still have far more questions than sure things on the starting staff, but Uwasawa will at least give them another wild card option at a negligible cost of acquisition.