Seahawks head coach Pete Carroll said Wednesday that Walker is having "a procedure" that's not related to a sports hernia, Curtis Crabtree of Sports Radio 950 KJR Seattle reports.
Per Crabtree, Carroll previously suggested that Walker was a dealing with a minor hernia issue, but evidently there's another injury in play for the rookie. Brady Henderson of ESPN.com reports that Carroll noted Walker doesn't have a core-muscle injury, but the exact nature of the running back's upcoming procedure is still a mystery. No matter the case, Walker is slated to miss some time in the preseason, but the Seahawks remain hopeful that he'll be ready to go for Week 1.