Manager Ron Washington said Stephenson continues to deal with right shoulder discomfort and may not be ready by Opening Day, Jeff Fletcher of The Orange County Register reports.
The 31-year-old appeared back on track for a high-leverage role to start the season after being slowed early in camp by shoulder soreness, but the renewed discomfort puts his availability in jeopardy. Stephenson's outlook will depend on how quickly the issue subsides, but a trip to the injured list to begin the campaign wouldn't be surprising.