It turns out that the Pittsburgh Pirates didn't lost right-handed reliever Deolis Guerra after all. The Cleveland Indians rescinded their waiver claim and Guerra returned to the Pirates. He has been placed on the 15-day disabled list due to left knee inflammation. To make room on the 40-man roster for Guerra, the Pirates designated pitcher Wilfredo Boscan for assignment.
Guerra was designated for assignment when Joakim Soria was added to the active roster last week. The Indians picked him up two days ago, but it looks like his medical issue caused them to change their mind. Boscan has been called up three times by the Pirates this year, but never got a chance to pitch, which would have been his Major League debut.