One-third of the way through their second season with Brian Callahan, the Tennessee Titans reached their breaking point.

On Monday, just one day after a 20-10 loss to the Las Vegas Raiders dropped Tennessee to 1-5, the team announced it had fired its head coach.

Callahan finishes his run with a 4-19 record. He becomes the first NFL head coach to be fired this season.

"After extended conversations with our owner and general manager, we met with Brian Callahan this morning to tell him we are making a change at head coach," Titans president of football operations Chad Brinker said in a statement. "These decisions are never easy, and they become more difficult when they involve people of great character. We are grateful for Brian's investment in the Titans and Tennessee community during his tenure as head coach. We thank him and his family for being exemplary ambassadors of the Tennessee Titans."

Mike McCoy, who had been the Titans' senior offensive assistant and was the San Diego Chargers' head coach from 2013-16, was named the interim head coach later on Monday.

Following the loss to the Raiders, standout defensive tackle Jeffery Simmons spoke critically of the team's preparation, saying the group was unable to capitalize on last week's surprising victory over the Arizona Cardinals.

"In this league, you have to learn how to be able to stack wins and carry that momentum over," Simmons said. "It started at practice. Just being honest, this was probably one of our worst weeks of practice. We came out flat Thursday. Sometimes things carry over."

Tennessee ranks last in the NFL in total offense after six weeks with just 232.3 yards per game.

Callahan faced mounting pressure early in the season as the team's margin of defeat expanded weekly. Following a 41-20 home loss to the Indianapolis Colts in which fans chanted "fire Callahan" before halftime, he relinquished play-calling duties to quarterbacks coach Bo Hardegree.

But the switch didn't alleviate problems, with Tennessee suffering a 26-0 loss to the Houston Texans in Week 4. The team was held scoreless for the first time since October 2019, and No. 1 overall pick Cam Ward was held to a season-low 108 yards on 10-of-26 passing.

"We're 0-4. At this point, we have nothing to lose," Ward said. "We've dropped a quarter of our (expletive) games and have yet to do anything. We have to lock in, especially myself. In all three phases, we have to play together and have not done it this year yet."

After being hired as the replacement to Mike Vrabel, whom the team will face Sunday when they host the New England Patriots, Callahan was expected to usher in a new era for the Titans with a more pass-heavy approach. But his debut season was marred by turbulent play from quarterback Will Levis and self-inflicted mistakes throughout the roster, as Tennessee tied for the NFL lead in turnovers with 34.

With the No. 1 overall pick in hand, Callahan and new general manager Mike Borgonzi took Ward. But Tennessee continued to be plagued by errors, and the team's -78 point differential is the second-worst in the league.

After the loss to Indianapolis, Colts wide receiver Michael Pittman Jr. said his team determined from pre-game introductions that the Titans were lacking in energy.

"They kinda looked a little sluggish. They were kinda walking around. Nobody was really bouncing," Pittman said. "Right then and there, we all sat there and were like, 'They don't want to play today.'"

This article originally appeared on USA TODAY: Brian Callahan fired by Tennessee Titans after 1-5 start

Reporting by Michael Middlehurst-Schwartz, USA TODAY / USA TODAY

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