Coach Kliff Kingsbury said Monday, however, that Brock's release "wasn't a one game type of situation."
"He gave us some good games and was injured and we're gonna play some younger players. We're always looking to turn over the roster and improve, and so that's kind of how it came about," he said.
Brock was signed on April 2 to a one-year contract. He started seven of the 10 games in which he was active.
He finished his time in Arizona with 37 tackles, two pass breakups, one batted pass and one dropped interception.
Arizona also released Zach Zenner, who was inactive the past two games after signing with the Cardinals on Oct. 23. He had two catches for minus-3 yards and one catch for 13 yards with the Cardinals.
The Cardinals are 3-8-1 and host the Pittsburgh Steelers on Sunday.