Red Sox pitcher Richard Fitts was having the best outing of his career on Saturday, until the injury bug bit the Boston righty in the bottom of the sixth inning against the Chicago White Sox.

Richard Fitts suffered a pectoral strain during Saturday's game against the Chicago White Sox, costing the Boston Red Sox one of their top young arms.

TAMPA — An MRI revealed Red Sox starter Richard Fitts has a mild right pectoral strain. He left his start Saturday against the White Sox in Chicago after five dominant innings. He had imaging done Monday.