The Steelers' already disappointing season suffered yet another hit. Their leading sacker, Cameron Heyward, is done for the season with a reported torn pectoral.

Heyward confirmed the news on Instagram, writing:

I would like to thank everyone who has been in my corner this season. It pains me to say that I will not get to continue playing this season. My role will change as I can not play but it will not change the goals the team has set out. My support for this team will only grow and I look forward in watching this team grow and fight on. Hate being on the sideline but there is a greater plan taking place. My patience will be tested but I look forward to 2017. My hand will remain in the pile no matter what!

That caption accompanied this photo:

A photo posted by Cam Heyward (@camhey97) on

Heyward isn't a big name outside of Pittsburgh, but he served as an important part of the Steelers' defensive front. Despite appearing in only seven games, he still led the team in sacks with three. He also notched four defended passes. Per Pro Football Focus, he registered 19 total quarterback pressures.

The Steelers are already struggling on defense. They're ranked 19th in DVOA and, against the Cowboys this past weekend, they were destroyed up front by the Cowboys' offensive line. Seriously, destroyed is not a hyperbole:

Next in line for the Steelers are Ricardo Mathews, seven-year veteran with four career sacks, and Javon Hargrave, the team's third-round pick in this year's draft. At 4-5, the Steelers are still alive in the AFC North, but they'll need to turn their season around in a hurry.