New Orleans also lost three starters on defense.
Kamara was hurt when he caught a pass for a 4-yard loss and his helmet collided with Falcons linebacker Deion Jones. Kamara walked into the tunnel to be evaluated. He was later ruled out.
Guard Senio Kelemete, filling in for starter Andrus Peat, left with a concussion and did not return. Josh LeRibeus, the backup center, replaced Kelemete. Peat was ruled out before the game with a groin injury.
Without Kamara, the Saints lose a runner with seven touchdowns and a 7-yard average on 86 attempts. In the passing game, Kamara has averaged 10.4 yards on 59 catches.
The Saints' defense lost linebacker A.J. Klein in the first half with a groin injury. Starting defensive end Trey Hendrickson left with an ankle injury and was ruled out. Strong safety Kenny Vaccaro was out with a groin injury.
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