Minnesota Twins pitcher Mike Pelfrey has had a difficult season so far, and it just got a little more difficult.

Pelfrey had surgery on Tuesday to relieve pressure on the ulnar nerve in his right elbow and will be sidelined 2-4 months, the St. Paul Pioneer Press reported.

Pelfrey signed a two-year, $11 million free agent contract with Minnesota over the winter. However, he is 0-3 with a 7.99 earned-run average in five starts.

He was placed on the disabled list in early May because of a groin injury.

Now he has more serious injury problems. The prognosis means he will be out at least until Auguast and may be out for the rest of the season.