Ian Rapoport reports it’s a torn patellar tendon for Peters, which means a lengthy rehab.
Expect Arizona to place Peters on injured reserve shortly.
Peters, 32, is a former third-round pick of the Falcons back in 2010. He was in the final year of his three-year, $10.5 million contract that when he signed a three-year, $12 million extension with Arizona in 2017.
After making a base salary of $3 million this year, Peters was set to be an unrestricted free agent in 2021.
In 2020, Peters has appeared in nine games for the Cardinals and recorded 15 tackles, two sacks and a pass defense. Pro Football Focus has him rated as the No. 65 interior defensive lineman out of 124 qualifying players.