Triple-A Gwinnett placed Waldrep (arm) on the 7-day injured list Tuesday.
Waldrep's move to the IL came just two days after he noticed a dip in velocity during a three-inning start versus Toledo. Specifics regarding Waldrep's injury remain vague, with Atlanta manager Walt Weiss merely noting that the right-hander experienced some arm discomfort during his most recent outing at Triple-A. Waldrep had coughed up 10 earned runs on 13 hits and 10 walks over 10.2 innings in three appearances (two starts) for Atlanta before he was demoted to Triple-A on July 10.