Oakland Raiders

In his first season as a head coach, Callahan led the Raiders to a third consecutive AFC West title and the franchise's first Super Bowl since returning to Oakland, making him just the fourth rookie head coach in NFL history to do so. The Raiders suffered a lopsided defeat in Super Bowl XXXVII losing 48–21 to the Tampa Bay Buccaneers coached by his former boss Jon Gruden. It did not help that the Raiders were without starting center Barret Robbins, the leader of their offensive line. Robbins went into a manic episode after not taking his medication, and spent most of the day before the game in Tijuana believing the Raiders had already won. When he finally resurfaced, he was so incoherent that Callahan had no choice but to leave him off the roster.^[12]

Callahan is the third Raiders head coach to win an AFC West title and lead his team into the conference championship game in his first full season. Only Art Shell (1990) and John Madden (1969) had accomplished this feat.

Under Callahan's guidance, the Raiders led the NFL in passing for the first time in team history and led the league in total offense for just the second time in team history.

During his tenure as not only head coach but also offensive coordinator for the Raiders, the Raiders offense led the league in rushing in 2000 and led the league in passing in 2002. In 2002, the Raiders became the first team to win games in the same season while rushing at least 60 times (against the Kansas City Chiefs in a 24–0 win) and passing at least 60 times (against the Pittsburgh Steelers in a 30–17 win). The Raiders offense also set many franchise records during this period, including fewest sacks allowed (28) in 2000, a mark that was broken the following year (27).

Despite the success of the 2002 team, the Raiders had a losing record in 2003. After the Raiders got off to a 2–5 start, many of the players, in particular Charles Woodson, publicly criticized Callahan, even suggesting that Callahan was deliberately trying to "sabotage the season".^[13] According to Woodson, the Raiders locker room was almost in a state of mutiny against Callahan, a claim corroborated by veteran receiver Tim Brown and others. Callahan, his supporters claim, had recognized that the team was aging and needed younger talent. To get it, he would have to cut existing salaries, an assertion that did not sit well with many of the team's veterans. It did not help that quarterback Rich Gannon was sidelined with injuries for much of the season. On November 30, after a 22–8 loss to the Denver Broncos, Callahan said the Raiders must have been "the dumbest team in America in terms of playing the game." After a lackluster 4–12 season, Callahan was fired by Raiders owner Al Davis.^[14] Even though the Raiders had gone all the way to the Super Bowl a year earlier, Davis was not known for being patient with his coaches. Callahan was the last Raiders head coach to post a winning season until Jack Del Rio in 2016.^[15]

Nebraska Cornhuskers

Soon after being fired by the Raiders, Callahan was hired at Nebraska. This would mark the first time in over four decades (since the hiring of Bob Devaney in 1962) that the Cornhuskers would be led by a head coach with no direct ties to the university either as a player or an assistant coach.

In his first season at Nebraska (2004), Callahan finished 5–6, giving the Cornhuskers their first losing season in more than 40 years. He had introduced the West Coast offense to a program that had traditionally relied on a strong option running attack.

The Cornhuskers finished 8–4 during his second season and won the 2005 Alamo Bowl by defeating No. 20 Michigan, 32–28. The 7–4 Wolverines were the highest-ranked opponent that Nebraska had defeated since a 20–10 win over No. 2 Oklahoma in October 2001. The Wolverines also were the highest-ranked opponent defeated by Nebraska away from home since a 66–17 win over Northwestern in the 2000 Alamo Bowl.

The 2006 team finished 9–5 and won the Big 12 North for the first time since 1999. The win over then No. 24-ranked Texas A&M marked Nebraska's first ever road win over a ranked Big 12 South team.

Many expected that the 2007 season would be a breakthrough year for Nebraska. However, the team fell well short of expectations. Nebraska was beaten by USC 49–31 in a nationally televised September 15 game, being outrushed by a 313 to 31 margin but outgaining USC in the passing game 389 to 144.^[20] A 41–6 thumping by Missouri started a five-game losing streak—the Cornhuskers' first since 1958.^[21] On October 15, 2007, Steve Pederson, the athletic director who had hired Callahan, was fired. Pederson was replaced on an interim basis by Nebraska's legendary former head coach, Tom Osborne.

On November 3, the Cornhuskers suffered a 76–39 pounding at the hands of Kansas. It was the most points a Cornhuskers team had ever surrendered at the time. The Cornhuskers followed this performance a week later with a win, scoring 73 points against Kansas State.

On November 24, 2007, a day after a 65–51 loss to rival Colorado, Callahan arrived at the team's practice facility at 6:30 a.m. He met briefly with Osborne and was fired. As he left the complex, he waved to reporters gathered outside. Osborne announced during a press conference held at the school that despite Callahan's ouster,^[22] he would still earn $3.1 million as part of his buyout.^[23]

While Nebraska's defense struggled during Callahan's tenure, numerous offensive school records were set (some of which could be attributed to the dramatic change in offensive philosophy) and quarterback Zac Taylor was named Big 12 Offensive Player of the Year for 2006. Callahan's tenure as Nebraska's head coach was primarily defined by an emphasis on recruiting (something many Nebraska fans felt was lacking during the previous coach's tenure^[24]). For example, with the assistance of his recruiting coordinator John Blake, Nebraska recruited defensive tackle Ndamukong Suh (2009 AP Player of the Year, Nagurski Trophy winner, Heisman Trophy finalist, etc.) although Suh later stated that he would "probably be at Oregon State right now" had Callahan not been fired.^[25] Callahan's 2005 recruiting class was rated as top-five by Rivals^[26] and ESPN analyst Tom Lemming said they were "No. 1, without a doubt.".^[27]

Despite a 27–22 record, Callahan's tenure is considered to be a failure. He led the Cornhuskers to two losing seasons in four years. He also finished ranked in a major poll only once in four years after the Huskers had only finished unranked once since 1962. Streaks such as 35 straight years in a bowl game and decades of consecutive wins against Kansas were lost in his 4 year tenure. He was 3–10 against teams ranked in the Top 25, 27–2 in games in which he led at halftime, 0–17 in games in which he trailed at halftime, 25–21 against Division I opponents, 15–18 against the Big 12, and coached the program its only two losing seasons (out of 4 seasons at Nebraska) in 46 years. Sports Illustrated named Callahan as the worst coaching hire of the decade in college football.^[28] Exacerbating Cornhusker fans' consternation with Bill Callahan's tenure at the university was his insistence that he had "done an excellent job in every area."^[29]

New York Jets

On January 18, 2008, Callahan was hired as assistant head coach of the New York Jets. On January 2, 2009 Callahan interviewed for the position of head coach of the New York Jets.^[30]

In 2008, three of the offensive linemen (with Bill Callahan as their position coach) from the Jets were named to the Pro Bowl: Nick Mangold, Alan Faneca and D'Brickashaw Ferguson. All three repeated in 2009. Under Callahan's direction of the running game the Jets broke the franchise record in 2009 gaining 2756 yards on the ground through 16 regular season games. They led the National Football League in rushing^[31] and averaged 4.5 yards per attempt.^{[citation needed]}

For the 2009 season, Peter King named Callahan the assistant coach of the year.^[32]

Dallas Cowboys

The Dallas Cowboys hired Callahan as their offensive line coach during the 2012 offseason. On June 4, 2013, Dallas owner Jerry Jones announced that Callahan would call plays on offense during the upcoming 2013 season, allowing head coach Jason Garrett to focus on game-management.^[33] After being the offensive coordinator for the Cowboys during the 2013 season, he was stripped of his play calling duties. During the 2014 off-season, the Cleveland Browns and Baltimore Ravens both asked Dallas for permission to interview Callahan for their open offensive coordinator positions, but Dallas declined.^[34] Dallas let Callahan's contract as offensive line coach expire after the 2014-2015 season, allowing him to seek other opportunities.^[35] At the time, Callahan was considered among the best offensive line coaches in the NFL, and some considered him to be the leading reason behind the success of the Dallas Cowboys offensive line, which had 3 linemen (Tyron Smith, Zack Martin, and Travis Frederick) named to the 2014 All-Pro Team.^[36]

Washington Redskins

On January 15, 2015, the Washington Redskins hired Callahan as their offensive line coach.^[37] On March 15, 2017, Washington promoted Callahan to assistant head coach in addition to his offensive line duties. On October 7, 2019, following a 0–5 start to their 2019 season, Washington fired head coach Jay Gruden and named Callahan the interim head coach for the rest of the season.^[38] Callahan went 3-8 in his stint as interim coach. The Redskins hired Ron Rivera shortly after the conclusion of the season.

Cleveland Browns

On January 31, 2020, Callahan was hired by the Cleveland Browns as their offensive line coach under head coach Kevin Stefanski.^[39] He missed the team's Wild Card playoff game against the Pittsburgh Steelers on January 10, 2021, due to COVID-19 protocols,^[40] but returned for the next playoff game.^[41]

On January 20, 2023, Callahan nixed an offensive coordinator interview he had had with the New York Jets and agreed to contract extension with the Browns.^[42]

Tennessee Titans

On February 13, 2024, Callahan was hired by the Tennessee Titans as their offensive line coach to work under his son, Brian, who was hired as the team's new head coach.^[43]

NFL

* – Interim head coach

College

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