Boston Red Sox

Tyler Thornburg likely headed for disabled list

Tyler Thornburg was acquired from the Brewers in December. Barry Chin / Boston Globe

SARASOTA, Fla. — Tyler Thornburg anticipated that Monday would be a critical milestone in his preparations for the season. But when the day arrived, it brought with it a setback that all but ensures that the Red Sox righthander — acquired from the Brewers to serve as the setup man in front of Craig Kimbrel — will open the year on the disabled list.

Thornburg, who hadn’t pitched in a Grapefruit League game since March 1 while trying to build shoulder strength, was scheduled to pitch against the Orioles, the first of what the Red Sox hoped would be at least three appearances in the final week of spring training. Instead, minutes before the game, the team announced that Thornburg had been scratched because of a spasm in his upper right trapezius muscle.

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The Sox already had acknowledged that Thornburg would have to thread something of a needle in order to be ready for Opening Day. After a scoreless inning in a minor league game last Friday, the 28-year-old expressed optimism that he’d be able to do just that. Monday’s setback, however, suggests that such ambitions will prove impossible to fulfill.

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