Lemieux (ankle) has been ruled out ahead of Monday's game versus Kansas City, Katherine Terrell of ESPN.com reports.
Lemieux has been unable to practice all week due to an ankle injury. His next chance at playing will be Week 5 against Tampa Bay on Oct. 13. The Saints signed veteran Connor McGovern from the Jets' practice squad to the active roster Friday, and although he has just two practices under his belt in New Orleans, he'll likely serve as the starting center for Monday's contest.