Upgrading the rotation has been an offseason priority for the Red Sox, who formally announced a one-year, $10 million agreement with right-hander Garrett Richards on Wednesday.

A 15-game winner for the Angels in 2015, Richards has spent his entire career to date on the West Coast, logging just 198 2/3 innings over the past five seasons due to injuries. He spent last year with the Padres, finishing 2-2 with a 4.03 ERA over 10 starts and four relief appearances.

¡°At this point in my career, winning is the main factor in the decision of where I want to play,¡± Richards said. ¡°A historic franchise like the Red Sox having interest in me, it made me want to come play for them. I looked at it like a challenge, playing in that division, but also going to a team that I know is going to score runs and have a lot of fun. These guys always look like they¡¯re having a blast.¡±

Richards underwent Tommy John surgery that cut his 2018 season short. He returned to make three starts for the Padres in ¡¯19 and was healthy during the shortened ¡¯20 season, holding right-handed hitters to a .189 batting average and .589 OPS. San Diego moved him to the bullpen from mid-September through the end of the year.

Richards said that he received positive reviews about Boston from infielder Mitch Moreland, a Padres teammate last season. To make room on the 40-man roster, Boston designated right-hander Joel Payamps for assignment.

¡°I put in a lot of time in rehab into getting back on the field and making sure that I can keep the same stuff I¡¯ve always had,¡± Richards said. ¡°I think that¡¯s just a credit to my hard work and the people who have been around me to help me get to this point. It¡¯s been a lot of hours, a lot of time and effort going into this to get me back on the field.¡±

In 187 career appearances, including 128 starts, Richards has compiled a 47-41 record with a 3.62 ERA. He projects as an important part of a rotation that will include Eduardo Rodriguez, Nathan Eovaldi, Nick Pivetta and Mart¨ªn P¨¦rez.

Earlier this offseason, the Sox landed another depth piece in righty Matt Andriese, who can start or relieve. Ace Chris Sale isn¡¯t expected back until around midseason, as he recovers from Tommy John surgery.

¡°I think it¡¯s solid, and when you get Chris Sale back, that¡¯s a huge addition to any rotation,¡± Richards said. ¡°It¡¯s going to be a chance for us to go out and pitch. I know that we¡¯re going to score runs; those are historic in Boston. I feel like every time I¡¯ve ever played Boston, there hasn¡¯t been any less than five runs scored.¡±

The 42nd overall pick by the Angels in the 2009 MLB Draft, the 32-year-old Richards enjoyed his best season in 2014, when he went 13-4 with a 2.61 ERA in 26 starts. His year ended early in a start at Fenway Park, when he injured his left knee while attempting to cover first base.

¡°It was a long time ago. It¡¯s something I¡¯ve put in the past,¡± Richards said. ¡°It hasn¡¯t really given me any issues since then.¡±

Richards has permitted only 0.75 home runs per nine innings over his career, the second-lowest mark in the Majors since 2011 (min. 500 innings). He averaged 95.1 mph with his fastball last season, throwing the pitch 46.3 percent of the time. He also utilizes a slider, sinker and curve, notching a 39.5 percent whiff rate with his slider.

¡°If I can get to a two-strike count without throwing somebody a slider, I think I¡¯ll have a pretty high success rate,¡± Richards said. ¡°I¡¯m excited to get there with my teammates and start building relationships. I think a good rotation is one that enjoys being around each other and enjoys talking about the game, so I¡¯m excited to start picking these brains.¡±