Mariners pitching prospect Danny Hultzen could be lost for much, if not all of the 2014 season after undergoing shoulder labrum and rotator-cuff surgery.

Hultzen had the surgery performed Tuesday by Dr. James Andrews in Pensacola, Fla. The surgery cleaned up the labrum and a partial tear of the rotator cuff while also repairing the shoulder’s capsule.

“This is very unfortunate for Danny and his family, but we have nothing but high hopes for a good recovery and rehab,” Mariners general manager Jack Zduriencik said in a release. “Danny is a tireless worker and will do everything he can to get back on the mound to start competing again.’’

No timetable has been given for Hultzen’s recovery, but return from such surgery can be tricky at best. In general, patients returning from a partially torn rotator cuff need at least three months to recover from the surgery and no longer feel any ache in the shoulder for six to eight months.

But full recovery from the injury can take a year or more. So it’s not known how long it would take Hultzen to be able to resume pitching at a professional level, nor how the labrum and capsule repairs might prolong his return.

Hultzen, 23, was drafted No. 2 overall by the Mariners in 2011 and had an outside shot at making the team in spring training before being sidelined with a minor hip problem.

His shoulder woes cropped up early in the Class AAA season, limiting him to six starts for the Tacoma Rainiers in which he went 4-1 with a 2.05 earned-run average. Hultzen made one additional rookie-level start as part of his recovery from his initial shoulder ailment.

The team revamped Hultzen’s throwing regimen in midsummer to try to lessen the strain on his arm. He was slated to pitch in this month’s upcoming Arizona Fall League, but was shut down when his arm troubles resumed while throwing in Instructional League ball.