Just a few days after it was revealed that Indianapolis Colts quarterback Anthony Richardson will likely miss the rest of the season due to a shoulder injury, it's the Colts' defense that has now taken a hit.

The NFL suspended starting defensive tackle Grover Stewart six games without pay for violating the league’s policy on performance-enhancing drugs.

"I want to apologize to the National Football League, the Colts organization, my teammates, our fans, and my family," Stewart wrote on Instagram. 

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"I was surprised and disappointed to learn I had violated the policy. I respect the integrity of the game and would never purposefully put myself or the team in this kind of situation. I am responsible for what I put in my body, and I should have taken the proper steps to educate myself. I will learn from this moving forward, and I will take the appropriate measures to ensure this never happens again."

Stewart has been a mainstay on the Colts' defensive line for years, missing just two games since he was a fourth-round pick out of Albany State in 2017. He has started 68 consecutive games and owns a Pro Football Focus grade of 75.2 this season. 

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Stewart is currently in the final year of a three-year, $30.75 million extension he signed back in 2020.

He will be eligible to return Dec. 4 when the Colts take on the Tennessee Titans.

In 102 career games, Stewart has recorded 259 combined tackles, 8.5 sacks and 32 QB hits, with most of his work coming from top-notch run-stopping in the middle of the defensive line alongside DeForest Buckner.

The Associated Press contributed to this report.