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The Boston Red Sox entered Sunday with the worst record (10-18) and run differential (-22) in the American League East. If they're going to climb out of the basement anytime soon, they'll have to do so with a severely compromised rotation. On Sunday, the Red Sox placed righty Michael Wacha on the injured list with left intercoastal irritation. In a corresponding move, Boston promoted Tyler Danish from Triple-A.

Wacha, who signed with Boston over the winter, had amassed a 1.38 ERA (289 ERA+) and a 1.73 strikeout-to-walk ratio in five starts this season. He's the fourth Red Sox starter to land on the shelf, joining James Paxton (Tommy John surgery), Rich Hill (COVID-19), and Chris Sale -- who, by the way, the team announced on Saturday had suffered a setback in his recovery from a fractured rib

"I think, roughly speaking, we were hoping to have him back around when he was eligible," chief baseball officer Chaim Bloom said about Sale's original June return timetable. "I think we're talking a few weeks [later] -- that's to have him back to start a major-league game."

The Red Sox rotation as it stands now includes Nathan Eovaldi, Nick Pivetta, Tanner Houck, and recent bullpen conversion Garrett Whitlock. It's unclear who the Red Sox would turn to if Hill is unable to make a quick return from the COVID-19 IL.

The Red Sox did add a veteran starter to their organization on Saturday, signing former St. Louis Cardinals right-hander Carlos Martínez to a minor-league pact. Martínez will report to Worcester, Boston's Triple-A affiliate.

Boston will wrap up its weekend series against the Chicago White Sox on Sunday before taking off Monday. On Tuesday, the Red Sox will kick off a five-game road trip that will include two in Atlanta against the Braves and three in Texas vs. the Rangers.