Two constants on the Steelers' defense this season have been the presence of Troy Polamalu in the Steelers' secondary and the shaky health-status of rookie linebacker Ryan Shazier.



Neither will play Sunday when the Steelers travel to New Jersey to take on the Jets in Week 10.



Polamalu (knee) was injured at the end of the first half in Pittsburgh's 43-23 win over the Baltimore Ravens in Week 9. He hadn't missed any playing time since the 2012 season before this, having played well over 1,000 consecutive snaps.



But it has been the opposite for Shazier, the team's first-round draft pick in 2014. He missed much of the team's Week 3 game against the Carolina Panthers with a knee injury, and had his ankle rolled over in a pile during the first half of the Ravens game. That was his third game back after the knee injury had cost him three games.



Will Allen took over for Polamalu during the game, as second-year safety Shamarko Thomas suffered another hamstring injury in Week 9. He's missed three games with the initial injury and this one is to his other hamstring. It would seem Allen is in line to make his first start of the season. He's well-experienced in this role, having filled in at both safety positions multiple times during the last two seasons.