According to a report from Manish Mehta, Jets safety Doug Middleton, who started yesterday's game, suffered a torn pectoral muscle.
Middleton missed the 2017 season with the same injury (on the other side), so will presumably be placed on season-ending injured reserve.
The Jets currently only have Jamal Adams and Terrence Brooks that are healthy on their 53-man roster. The other starter, Marcus Maye, should be out for a few more weeks.
Potential replacements include Rontez Miles, who is eligible to come off the PUP list now and JJ Wilcox, who is still a free agent having been released a few weeks ago.
The Jets also have undrafted rookie Brandon Bryant and cornerback Jeremy Clark, who played some safety in college, on the practice squad and Todd Bowles likes all his defensive backs to be able to play all secondary positions so someone like Juston Burris could theoretically be used at safety in an emergency.