Geno Smith will start, and Manning will be the backup, as coach Ben McAdoo detailed throughout the week. Manning will be the contingency plan should something happen to Smith.
Webb will be inactive for the 12th straight game.
Manning started 210 consecutive regular-season games for the Giants prior to Sunday. Smith will be looking to start and play his first full game in almost three calendar years.
The thinking is that Webb, a third-round pick out of the University of California, is not quite ready. The Giants hope that changes sooner rather than later. Webb has served mostly as the scout-team quarterback at practice this season, and his role did not change this week after the Giants made the decision to go with Smith as the starter.
"Yeah, we're going to address that soon," McAdoo said Friday.
The Giants (2-9) have insisted that part of the plan is to have Webb play some time in the final few weeks of the season.
"I will tell you that Davis should play at some point, and when that is, I don't like to interfere with those things. I'd like the coach to make that decision," co-owner John Mara said this week. "But I think he knows what our feeling is."
McAdoo would not reveal the plan Friday, though he said there was one in place. He declined to specify whether Webb would dress Sunday for the first time in his professional career.
Webb could be made active next week, when the Giants host the Dallas Cowboys in their first home game since 2004 without Manning as the starter.