KANSAS CITY, Mo. (AP) Royals pitcher Danny Duffy underwent surgery Tuesday to remove loose debris in his pitching elbow, and the left-hander is expected to resume his normal offseason training in about six weeks.

The Royals said that Duffy should be ready for spring training in February.

Duffy has been dealing with minor pain in his elbow for a couple years, but loose cartilage and bone chips had begun to cause inflammation. He landed on the disabled list in late August but returned to make three starts down the stretch in September.