(CBS) The White Sox are calling John Danks’ shoulder injury a “mild Grade 1 strain of the subscapularis muscle” and say he could begin a rehab assignment in 3-4 weeks.

The left-hander referred to the injury as a “tear” Monday night, but said he did not need surgery.

Danks had two MRIs performed Monday at Rush University Medical Center, one with contrast and one without contrast. The results revealed the strain, but showed no tendon or ligament damage and his labrum is intact. The White Sox also say the strain has shown improvement from the previous MRI performed May 23.

Danks will rest until Friday when he will begin a rehabilitation and strengthening program with trainer Herm Schneider.

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