Waldichuk (elbow) could begin a rehab assignment sometime next week, Martin Gallegos of MLB.com reports.
The lefty has joined the Athletics on their road trip and will throw four bullpen sessions before being sent out on a rehab assignment. Waldichuk was diagnosed last October with a UCL sprain and flexor strain, but he chose a more conservative Tenex procedure to remove scar tissue and help alleviate pain. He will be built up as a starter, so Waldichuk will likely need most of his 30-day rehab allotment before being an option for the Oakland rotation. The southpaw is on the 60-day injured list and won't be eligible for activation until late May.