Williamson (shoulder) will be shut down from throwing for at least seven days, Charlie Goldsmith of The Cincinnati Enquirer reports.
The left-hander was pulled off his rehab assignment due to persistent issues with his shoulder, and he'll stop throwing entirely for at least a brief period while he and the club consider different options for how to proceed with his recovery. Williamson has yet to pitch for the Reds this season due to the shoulder sprain, and it's now questionable whether he'll be able to return ahead of the All-Star break.