The person spoke to USA TODAY Sports’ Bob Nightengale on the condition of anonymity because the signing wasn’t yet official.

The left-hander joins the National League champions’ rotation that already features Zac Gallen and Merrill Kelly, forming a formidable front three in Phoenix.

The Tigers had signed Rodriguez to a five-year, $77 million deal before the 2022 season, the same winter that Detroit added shortstop Javier Baez for $140 million. He pitched quite well for the Tigers (3.58 ERA in 43 starts), but missed half of his first season in Detroit.

Rodriguez debuted for the Red Sox as a 22-year-old in 2015 and spent years with the club, compiling a 4.16 ERA in 159 games. Rodriguez helped Boston win the World Seres in 2018, making seven appearances in the postseason.

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He sat out the shortened 2020 season, getting diagnosed with myocarditis following a COVID-19 positive.

Behind Gallen, Kelly and now Rodriguez, right-hander Brandon Pfaadt is expected to be a regular in the rotation after impressing (3.27 ERA in five starts) as a rookie during Arizona’s run to the World Series.