Left-hander Rich Hill agreed to a one-year, $6 million deal with the Oakland A's on Tuesday night, a league source told Yahoo Sports, capping a tremendous ascent in which the 35-year-old went from independent league afterthought to major league multimillionaire in a matter of three months.

After signing with Boston out of the Atlantic League in August and pitching at Triple-A for a month, Hill made four starts with the Red Sox in September and impressed enough that a half-dozen teams made offers similar to Oakland's, which is pending a physical. Over 29 innings, Hill struck out 36, walked five, yielded 14 hits and posted a 1.55 ERA.

Hill is believed to have turned down more money than Oakland offered because of the A's likelihood to use him in their rotation. Oakland's pitching depth – in addition to Hill and ace Sonny Gray, they have young starters Jesse Hahn, Chris Bassitt and Kendall Graveman, top prospect Sean Manaea and veteran Jesse Chavez. Multiple teams have shown interest in Chavez, sources said, and the signing of Hill makes him a potential trade candidate, especially as he enters his final season before free agency.

The signing of Hill represents a minor risk with major upside for Oakland. If he pitches like he did toward the end of last season, a 1-2 punch of Gray and Hill – the A's have insisted to other teams they will not entertain trading Gray, league sources said – is mighty potent. Should he falter in a starting role, Hill can be a devastating left-handed piece out of the bullpen. And if injuries befell him, it's a one-year deal, the sort that won't weigh on a team for years to come.

For Hill, Oakland is a similarly strong fit. Not only does he get to throw in one of the game's best pitchers' parks, Hill will make nearly twice his previous career earnings in 2016 alone.

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