Marlon Mack suffered a season-ending torn Achilles during the Indianapolis Colts' Week 1 loss to the Jacksonville Jaguars.

Mack suffered the injury after catching an underneath pass in the second quarter. He immediately grabbed his ankle, got up and took off his helmet before waving for assistance from the Colts' sideline.

Mack is in the final season of his contract as the Colts didn't offer him an extension in the offseason.

The Indianapolis Colts have signed Ryan Kelly to a four-year, $50 million extension that includes $34 million in guaranteed money.

The deal is the NFL's richest for a center.

"Feels good to be rewarded," Kelly said. "I want to live up to the contract I signed. Go out every single day, be the leader on the offensive line they I know I can be. Play with the consistency I can play with and stay healthy. Those are the things that drive me every single day."