The relationship between New York Giants coach Brian Daboll and defensive coordinator Wink Martindale came to an explosive end Monday, less than 24 hours after the team finished a disappointing 6-11 season.

Neither side looked good as details emerged about the final hours of their partnership, with Daboll’s firing of Martindale’s two most trusted assistants, Kevin and Drew Wilkins, and Martindale’s responding by saying, “F— you” and storming out of the room, according to team sources granted anonymity by The Athletic because they are not authorized to discuss the situation publicly. The Giants announced Wednesday the sides had “mutually agreed to part ways.”

Even in a decade full of dysfunction, the Martindale blowup stands out as a low point for the Giants. Such an ugly departure leads to an obvious question: How could a relationship that appeared so promising dissolve into such acrimony?

Martindale was available for Daboll to hire in 2022 after a surprising departure from the Baltimore Ravens after 10 years as an assistant, including a top-three scoring defense in three of four seasons as defensive coordinator. A contractual stalemate and a desire for a fresh start led to Martindale’s exit from Baltimore.

Martindale had options, but he was drawn to the Giants due to his fondness for ownership after interviewing for the team’s head-coaching vacancy in 2020. The 60-year-old Martindale has made no secret of his desire to become a head coach, and he saw success in New York as a pathway to reaching that goal.

Daboll and Martindale didn’t have a pre-existing relationship beyond squaring off as coordinators. That competition created a mutual respect, and they found they had similar personalities when they started working together.

“I’ve always respected him,” Martindale said last January. “I think we’re very similar personality-wise. You know that when you meet somebody.”

Despite similar wiring as hyper-competitive football lifers, Daboll and Martindale brought different temperaments to the sideline. And it didn’t take long for those differences to surface, with tension starting to build during their first training camp together.

“You could probably see it building a little bit,” a team source said. “Like the defense is getting installed and you might have 12 guys on the field and Dabes is losing it, and he’s calling out coaches, and he’s making it personal.”

Martindale presents a brash persona, cultivated with his standard attire — sunglasses, long-sleeve white compression shirt and basketball sneakers — that makes him look like a WWE rendition of a football coach. But he prides himself on his composure.

Though it’s not uncommon for NFL head coaches to lose their cool, multiple team sources said Daboll goes overboard, particularly during games.

“On game day, he’s a madman,” one team source said. “It’s just brutal.”

That shouldn’t come as a revelation to fans who have witnessed Daboll’s red-faced tirades directed at players for mistakes during games. And it has rankled assistants to have to endure Daboll’s rants while they’re trying to coach.

“It’s to the point where you’ve got to take your headsets off or take one ear off,” another team source said. “He’s just constantly screaming. It’s like, ‘Jeez, I can’t even think.’”

Martindale spent the previous decade working for Ravens coach John Harbaugh, who has a much calmer sideline demeanor. Martindale didn’t appreciate the change to Daboll’s style.

“Wink didn’t like that at all,” a team source said. “The stares and how he just kind of looks at you, Wink couldn’t stand it.”

Martindale’s philosophical differences were hiding in plain sight to outsiders as early as October 2022. His comments in a news conference now read like thinly veiled criticisms of Daboll’s sideline outbursts.

“What I tell the players all the time is, ‘What I owe you during the game is my composure,’” Martindale said. “There’s some people telling me I need to be more animated on the sidelines. You’re not going to be animated if you’re thinking about the next play, what you’re going to call next.”

Martindale was more overt about his displeasure with Daboll’s eruptions behind the scenes.

“Wink would just walk in (to a coaches’ meeting) and say something like, ‘When such and such did this, I stayed calm. I just went onto the next play,’” a team source said. “He’d throw stuff out there and see if he could get (Daboll) riled up. Dabes knows it. Dabes isn’t stupid. It would just float on by in the meeting, and nobody would say anything.”

As evidenced by his explosive departure, Martindale isn’t the type to quietly endure something he doesn’t like. So there were the snide comments in meetings and the public allusions to his preferred coaching style.

“His personality kind of fits his style of defense — blitz zero, man coverage,” a team source said. “He’s not a loose cannon. He’s very calculated. But he just doesn’t give a s—.”

The rift was minimized last season by the ultimate salve: winning. The Giants unexpectedly raced out to a 6-1 start, with Martindale’s blitz-happy scheme contributing to victories over former MVP quarterbacks Baltimore’s Lamar Jackson — a particularly sweet win over Martindale’s former team — and Green Bay’s Aaron Rodgers.

The Giants made the postseason and won their first playoff game since Super Bowl 46 in 2012. No one outside of the team had any reason to suspect dissension between Daboll and Martindale.

“When it’s going good, you put up with it,” a team source said. “When it’s not going good, it compounds.”

Most observers believed the Giants’ misery this season started with their 40-0 Week 1 loss to the Dallas Cowboys in front of a national audience on “Sunday Night Football.” But a team source said there was an extraordinary amount of tension on the sideline during the Giants’ preseason opener in Detroit.

Even with most of the starters resting, Daboll was incensed by mistakes made by players who wouldn’t make the roster. The TV broadcast captured Daboll giving special teams coordinator Thomas McGaughey, who was fired Monday, a death stare after the Giants allowed a 95-yard punt return for a touchdown in the third quarter of the 21-16 loss. The entire staff felt Daboll’s wrath during that exhibition game.

Brian Daboll’s 👀 at Giants special teams coordinator Thomas McGaughey after that 94-yard punt return for a TD by the Lions. 🥶 pic.twitter.com/PWEo5Bk9yL

— Ralph Vacchiano (@RalphVacchiano) August 12, 2023

“That kind of set the tempo for the year,” a team source said.

The Giants never recovered from a disastrous 1-5 start. The offense, which drew much more of Daboll’s attention, was a mess. But the defense wasn’t much better during the rocky opening stretch. The Giants allowed 441 yards in a 30-12 loss to the San Francisco 49ers in Week 3 and 524 yards in a 31-16 loss to the Miami Dolphins in Week 5.

The season bottomed out with a 30-6 loss to the Las Vegas Raiders in Week 9. Quarterback Daniel Jones tore his ACL in the game, but drama from the defense surprisingly drew the spotlight.

Safety Xavier McKinney told ESPN of the coaches, “I don’t think they’ve done a great job of letting the leaders lead and listening to the leaders and the captains.” Consistent with how he handles any hint of controversy, Daboll downplayed McKinney’s comments the next day. McKinney said “everything is good” two days later.

The story could have ended there. But during his news conference later that week, Martindale spoke extensively about how hurt he was by McKinney’s comments, creating another cycle of headlines. It was the opposite of Daboll’s approach.

The growing tension boiled over during a 49-17 loss to the Cowboys the next week. With undrafted rookie quarterback Tommy DeVito’s making his first career start, the Giants were steamrolled by the Cowboys. Dallas gained 640 yards as the Giants’ record dropped to 2-8.

Fox sideline reporter Tom Rinaldi noted on the broadcast that Daboll and Martindale engaged in a lengthy discussion that started at the end of the first half and continued as they came out of the locker room for the second half. Tensions were running high as the Giants got destroyed by their rival for the second time in two months, with numerous “animated discussions” on the sideline between players and coaches.

All of the simmering discord came pouring onto the surface before the Giants’ Week 12 game against the New England Patriots when Fox’s Jay Glazer reported that the relationship between Daboll and Martindale was in such a “bad place” that a split was expected. After a dominant defensive performance sparked a 10-7 win over the Patriots later that day, Daboll gave Martindale a game ball in the locker room in a presentation that was viewed as performative by team sources who knew the relationship was fractured.

🗣 Postgame speech pic.twitter.com/SwunL7mKzp

— New York Giants (@Giants) November 26, 2023

Impressively, Daboll and Martindale managed to mostly shield the players from their feud. That was important to keeping the team together during a surprising 4-3 finish with DeVito and veteran backup Tyrod Taylor at quarterback.

Players view Daboll as a players’ coach, even though they can be on the receiving end of his sideline explosions. A veteran player said the outbursts are mostly an accepted part of playing for Daboll, even though they can be counterproductive in situations when emotions are already running high.

Players complained that Daboll’s predecessor, Joe Judge, worked them too hard in practice and held excessively long meetings. Daboll seems to have a better sense of how to manage players, with lighter practices and shorter meetings. The Giants held a rare Wednesday walk-through in Week 18 and then delivered a spirited effort in a 27-10 season-ending win over the Philadelphia Eagles.

“He does a good job of keeping everybody together and feeling the pulse of the team,” a team source said.

That touch will be needed now more than ever with his staff. Daboll must find a new defensive coordinator and fill a handful of other assistant jobs that were opened during a mini-housecleaning Monday.

The problem with Martindale has been eliminated, as the veteran coach is free to seek employment from any team after agreeing to sacrifice the $3 million remaining on his contract with the Giants, a league source said. But as Daboll embarks on a pivotal offseason, it will be interesting to see whether the dynamics that led to the ugly divorce with his most prominent assistant cause him to make any changes.

“I’m confident in what we do, how we do things,” Daboll said Monday, hours before everything blew up. “Certainly, there’s a lot of things that we can improve. That’s what the offseason is for, really, in every aspect.”

(Illustration: John Bradford / The Athletic; photos of Brian Daboll and Wink Martindale: Kevin Sabitus, Stephen Maturen / Getty Images)

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