Co-owner John Mara said the team felt a shift in gears was unavoidable after meeting Steve Tisch following Sunday's loss in Oakland.
"We agreed wholesale that changes needed to be made to this organization to get us back to the team we expect to be," he said. "We also agreed that it was pointless to wait any longer to make these changes."
Mara said both interim general manager Kevin Abrams and interim head coach Steve Spagnuolo are both candidates for full-time positions. He added that ex-Giants GM Ernie Accorsi will be a consultant on the search.
Mara said the GM search would begin immediately and "in all likelihood" that position will be named before a head coach.
Less than a month after issuing a statement that the team would make no changes to the coaching staff until after the season, the Giants pulled a U-turn Monday.
"I changed my mind, we changed our minds," Mara said of reversing course. "Given all the events that have occurred, where we are as a franchise right now. To be honest with you, it became more and more apparent that we were going to have to do something at the end of the season. So we talked after the game and again this morning about why prolong it any longer. Why not just get it done now? I'm very conscious of the fact that three of our last four games are at home. I was conscious, having lived through it before, of what the reaction was going to be. It also gives us somewhat of a tactical advantage, allowing us to start looking at general managers right now rather than waiting to the end of the season."
"I signed off on that..." Mara said explaining the process that led to Manning missing his first start in 210 games. "You ought to stop blaming Ben and Jerry on that, if you want to blame anyone on that, blame me. I certainly had the power to overrule it if I wanted to. I chose not to do it."
"It's really been a perfect storm this season," Mara said. "Everything that could have gone wrong has gone wrong so far this season. It's just one of those things you just have to live through, and suck it up, and make whatever changes you have to make and go on."