Mena (shoulder) had been scheduled to resume his throwing program two weeks ago, MLB.com reports.
Mena, who has been on the shelf all season while recovering from a right teres major strain, initially began a throwing program in late April before being shut down for a brief period. Though the right-hander appears to be building back up again, the Diamondbacks haven't provided an indication of where exactly he stands in his progression. Considering that he'll eventually need to complete a lengthy rehab assignment before being activated from the 60-day injured list, Mena is most likely at least a month away from joining the Diamondbacks.