The Texas Rangers acknowledged on Tuesday that left-hander Derek Holland underwent microfracture surgery on his left knee last week, an involved procedure that will make it challenging for him to meet the club’s goal of a mid-season return.

The last Rangers’ pitcher to undergo microfracture surgery needed more than seven months before re-surfacing in the majors. Right-hander Scott Feldman had the surgery on the right femur on Nov. 3, 2010. After two minor-league rehab assignments, Feldman came off the disabled list on July 14, 2011. Holland had surgery on the kneecap, which bears less weight than the femur.

In the surgery, holes are created in the bone, and the fractures are sealed with blood and bone marrow to create an over-sized clot that will stimulate the growth of new cartilage. The surgery has been more common for NFL and NBA players than baseball players.

Dallas Cowboys defensive end Anthony Spencer did not play this season after having the surgery on Oct. 1 and continues to rehabilitate. Center Greg Oden, the first pick in the 2007 NBA Draft, has appeared in only 82 career games, the last on Dec. 5, 2009, since undergoing the procedure.