Doctors operated on Trevor Rosenthal Thursday:

Oakland Athletics right-handed reliever Trevor Rosenthal underwent surgery on Thursday after he was diagnosed with severe neurovascular compression.

The procedure, involving the removal of Rosenhal’s first rib, a pec minor release and scalene release, was performed by Dr. Gregory Pearl in Dallas, Texas.

ESPN.com

I wonder if this was bothering him at the start of the 2019 season when he pitched so poorly for the Nationals. It could be the extra time off before the start of the 2020 season helped the condition get better? Either way, here is wishing Rosenthal a quick recovery.