The Giants announced early in the second quarter that it is unlikely that Kiwanuka will return.
"This is not serious at all," Kiwanuka told the NBC game telecast. "It is one of those things that in the preseason you want to make sure you are healthy. Confident I will be back when the season starts if not sooner than that."
Kiwanuka is a starting outside linebacker but also moves to defensive end on third downs as well. Clint Sintim came in and replaced Kiwanuka.
Kiwanuka played in just three games last year due to a herniated disc in his neck. He did not have surgery and was cleared by doctors to resume playing again earlier this year. Kiwanuka was converted back to a linebacker this season from his defensive end position.
Defensive end Justin Tuck also suffered a "burner." He underwent X-rays and the news was positive.
Ohm Youngmisuk covers the Giants for ESPNNewYork.com.