The Red Sox will demote right-hander Clay Buchholz to the bullpen and activate left-hander Eduardo Rodriguez, according to manager John Farrell (via reporters). Rodriguez will start Tuesday in Baltimore.
Buchholz, 31, has been terrible for the Red Sox this season, posting a 6.35 ERA while the team is 3-7 in his starts. Buchholz has allowed 12 home runs so far this year, trailing only Max Scherzer (14) and Chris Young (13) in that league-wide category.
Rodriguez has yet to make his major-league debut after suffering a knee injury in spring training. The southpaw posted a 3.54 ERA in 28 innings of rehab at Triple-A Pawtucket, and will immediately slot into a rotation that includes David Price, Joe Kelly, Rick Porcello and Stephen Wright.
Rodriguez made his major-league debut last season, going 10-6 with a 3.85 ERA in 21 starts after being promoted in late May. He was originally acquired by the Red Sox from the Orioles in a 2014 trade deadline deal involving reliever Andrew Miller.