Jameson (elbow) has been throwing from up to 90 feet, Alex Weiner of ArizonaSports.com reports.
Jameson has been sidelined by a UCL strain since July 7 and is currently on the 60-day injured list. While a return is still well in the future, manager Torey Lovullo said that there is hope that Jameson will be able to take the mound again in the current campaign.