The Mariners added some experienced depth to their pitching staff Thursday, signing right-handed reliever Yoshihisa Hirano to a one-year contract and agreeing to terms with left-hander Wei-Yin Chen to a minor-league contract with an invite to spring training.

To make room on the 40-man roster for Hirano, Seattle designated left-handed pitcher Ricardo Sanchez for assignment. The Mariners now have seven days to trade, release or outright Sanchez’s contract.

Per multiple reports, Hirano will make $1.6 million with performances bonuses.

“We’re glad to have Yoshi on board,” Mariners general manager Jerry Dipoto said in a news release. “We believe his combination of experience and bat-missing ability brings needed stability to our bullpen.”

A MLB source confirmed the Mariners had reached an agreement with Chen pending a physical. The team is expected to make the signing official in the next few days.

Even with the addition of Hirano and Chen, the Mariners are still expected to add possibly another reliever and a starting pitcher before pitchers and catchers report to spring training on Feb. 12.

Hirano, 35, pitched for 11 seasons in Japan’s Nippon Professional Baseball for the Orix Buffaloes before signing a two-year contract with the Arizona Diamondbacks before the 2018 season. 


Last season, he posted a 5-5 record with a save and a 4.75 ERA (28 earned runs, 53 innings pitched) with 22 walks and 61 strikeouts in 62 relief appearances. 

The Mariners are hoping Hirano can find his production from two seasons ago.

In 2018, he went 4-3 with three saves and a 2.44 ERA (18 ER, 66 1/3 IP), while striking out 69 and walking 23 in 75 appearances. Among qualified relievers, his 2.44 ERA, was the 14th-lowest in the NL. If he can replicate that success, the Mariners will likely trade him at the deadline.

Chen was once a promising pitcher for the Orioles, who signed a five-year, $80 million contract with the Marlins as a free agent before the 2016. But Chen never lived up to the contract, producing four largely ineffective and injury-filled seasons. He posted a 13-19 record with a 5.10 ERA in 53 starts and 15 relief appearances.  Miami is still paying Chen $22 million this season.

He will compete for the fifth spot in the rotation and could pitch in a swing role in the bullpen. It’s possible he will end up in the rotation at Class AAA Tacoma.

Sanchez, 22, spent the 2019 season with Double-A Arkansas where he went 8-12 with a 4.75 ERA (72 ER, 146.0 IP) with 38 walks and 135 strikeouts. He set career-highs in starts (27), innings pitched (146.0) and strikeouts (135). His 135 strikeouts were second-most in the Texas League, trailing only Justin Dunn (158).

But he’s also out of minor-league options, meaning he was likely to be designated for assignment this spring when he didn’t make the Mariners’ opening-day roster.

Sanchez was acquired by the Mariners from the Braves in exchange for cash considerations on Nov. 29, 2018. He was originally signed by the Angels as a non-drafted free agent on July 2, 2013. He was acquired by Atlanta from the Angels in exchange for right-handed pitcher Nate Hyatt and infielder Kyle Kubitza on Jan. 8, 2015. In six minor-league seasons between the Angels (2014), Braves (2015-18) and Mariners (2019) organizations, he is 25-47 with a 4.52 ERA (260 ER, 517 1/3 IP) in 111 games (106 starts).