EAST RUTHERFORD, N.J. (CBSNewYork) — The Giants have started to clean house before their tumultuous season is even over, firing coach Ben McAdoo and general manager Jerry Reese Monday with four games left to play.

“We agreed that wholesale changes needed to be made to this organization to get us back to the team that we expect to be,” co-owner John Mara said at an afternoon news conference, referring to himself and co-owner Steve Tisch. “And we also agreed that it was pointless to wait any longer to make these changes.”

Defensive coordinator Steve Spagnuolo, a former St. Louis Rams head coach, will take over as the interim head coach of the 2-10 team. Longtime assistant general manager Kevin Abrams will serve as interim GM. Both will be candidates for those positions full-time, Mara said.

MORE: Who Will Be Next Head Coach Of Giants? Here Are Some Potential Candidates

It is a dramatic fall for McAdoo. Previously the Giants’ offensive coordinator, McAdoo replaced Tom Coughlin before the 2016 season and enjoyed instant success, leading the Giants to an 11-5 record and a postseason berth. That showing sparked Super Bowl talk from both Giants fans and the media before this season.

But the year got off to a disastrous start, with the Giants losing their first five games. Then in a Week 5 game at home against the Los Angeles Chargers, the Giants lost wide receivers Odell Beckham Jr., Brandon Marshall and Dwayne Harris to season-ending injuries and wideout Sterling Shepard for a time as well.

Ben McAdoo

Giants coach Ben McAdoo looks on from the sideline during a game against the Denver Broncos on Oct. 15, 2017, at Sports Authority Field at Mile High in Denver. (Photo by Dustin Bradford/Getty Images)

McAdoo’s seat grew hotter with each loss, particularly following an embarrassing 51-17 loss to the Los Angeles Rams at home in Week 9 and a 31-21 road loss to the previously winless San Francisco 49ers in Week 10.

MORE: Palladino: Unapologetic McAdoo Had This Firing Coming

“I never would’ve dreamt this in a million years back in September that this would be happening, particularly during the season,” Mara told WFAN’s Mike Francesa.

“I thought this was as good a roster as we’ve had in many years and felt very confident going into this season, as did most people around the league about our roster.”

With the season slipping away, McAdoo appeared to struggle to keep a handle on his players, suspending cornerbacks Dominique Rodgers-Cromartie and Janoris Jenkins for violating team rules.

Then last week, McAdoo announced Geno Smith would start over Eli Manning in Sunday’s game at Oakland, which was met by a swift backlash from fans who supported the two-time Super Bowl MVP quarterback.

Mara, however, insisted it did not play a role in the decision to fire McAdoo.

“Two and 10 is 2-10, and obviously the public reaction to that was not pleasant, but that really didn’t have any effect on our decision,” Mara told reporters.

MORE: Report: Eli Manning To Start Against Cowboys Sunday

“You ought to stop blaming Ben and Jerry on that,” the Giants owner added. “If you want to blame anybody for that, blame me because I certainly had the power to overrule it if I wanted to. I chose not to do it.”

Mara and Tisch released a statement last month indicating they would wait until after the season to make any decisions about McAdoo’s fate. But on Monday, Mara said they had changed their minds.

“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?” said Mara, adding he would not tolerate any talk of tanking. “I’m very conscious of the fact that three of our last four games are at home. I was conscious of, having lived through it before, of what the reaction was going to be. Also, it gives us somewhat of a tactical advantage in allowing us to start looking at general managers right now rather than waiting until the end of the season.”

McAdoo, 40, finishes his tenure with a 13-15 record.

“I think he’s going to learn from his experience here, and he’ll go on to be a successful head coach,” Mara said.

Reese had been with the Giants since 1994, working his way up from a part-time scout to eventually general manager, a role he assumed in 2007. He led the front office during two Super Bowl championship seasons, after the ’07 and ’11 seasons.

Jerry Reese

Giants general manager Jerry Reese (Photo by Joe Robbins/Getty Images)

He had his moments in picking personnel, drafting future star players such as Jason Pierre-Paul, Justin Pugh, Odell Beckham Jr. and Landon Collins. And his free-agent signing class in March 2016 — which included defensive end Olivier Vernon, defensive tackle Damon Harrison and Jenkins — helped turn around a Giants defense that was previously ranked last in the NFL, fueling their run to the playoffs.

But in recent years, Reese has come under fire for selecting disappointing offensive tackle Ereck Flowers with the ninth overall pick in the 2015 draft and not doing enough to address the team’s offensive line woes.

“I don’t think there was any one final straw,” Mara said of firing Reese. “I just think where we are as a franchise right now — we’re 2-10, we’ve kind of been spiraling out of control here — I just felt like we needed a complete overhaul.

Mara said the search for a new general manager will begin immediately and former GM Ernie Accorsi will be a consultant in the process. Mara said he hopes to hire a general manager before a coach. He said he prefers not to hire someone who would assume both rules, but added “never say never.”

More From CBS New York

CELEBRATING 50 YEARS
Get Our Morning Briefs
Bloomberg WCBS Tri-State Business Index

Watch & Listen LIVE