Alvarez (head) passed the concussion protocol Wednesday and will fly back with the team to New York, Anthony DiComo of MLB.com reports.
Alvarez left in the sixth inning of Wednesday's 5-0 loss to the Padres after a foul tip deflected off his catcher's helmet. He was able to avoid a concussion diagnosis, and with the Mets off Thursday, he could be back in the lineup for Friday's weekend series opener against the Giants.