Conflicting reports are coming out of South Korea regarding the severity of an elbow injury suffered by U.S. goalkeeper Kasey Keller. Korean news agency Yonhap cited sources from the Asan Medical Center suggesting that the injury could force Keller to miss World Cup games. The sources said X-rays revealed no broken bones, but that Keller was in too much pain to under an MRI, which would reveal whether he had torn muscle. The Associated Press reported that a left elbow sprain forced Keller to leave WednesdayÆs practice and that team doctors said the injury was ''minor.'' ''Kasey was checked out by the doctors after tweaking his arm,'' said U.S. Soccer spokesman Jim Moorhouse. ''The doctors said it is not expected to sideline him at all.''