Philadelphia Eagles McDermott originally joined the
Philadelphia Eagles in
1999 as a scouting administrative coordinator, a position he held until being promoted to
Andy Reid's coaching staff in
2001. He became defensive quality control coach and later assistant defensive backs coach. In
2004, McDermott helped replace
Steve Spagnuolo by serving as assistant defensive backs coach, as Spagnuolo was assigned the linebackers coach position. That same year, McDermott saw both of his starting safeties (
Brian Dawkins and
Michael Lewis) earn
Pro Bowl berths for the first time in team history. McDermott and the Eagles appeared in
Super Bowl XXXIX that season but lost to the
New England Patriots, who won their second straight Super Bowl title. Under McDermott's watch, Dawkins went on to earn two more Pro Bowl berths following the
2005 and
2006 seasons. In
2007, McDermott was assigned
linebackers coach, after Spagnuolo had left to take the defensive coordinator job for the
New York Giants. On January 28, 2008, Eagles head coach
Andy Reid named McDermott as the secondary coach. On May 18, 2009, McDermott was named the interim defensive coordinator as a result of defensive coordinator
Jim Johnson's medical leave of absence. Two months later on July 24, due to the continuing decline of Johnson, the Eagles announced McDermott would take over as full-time defensive coordinator. Johnson died four days later. Thanks in part to what he learned under Johnson, McDermott would go on to implement a variety of blitzes in his later defensive gameplans. McDermott was fired as the defensive coordinator on January 15, 2011, after 12 years with the Eagles.
Carolina Panthers McDermott was hired as the defensive coordinator of the
Carolina Panthers on January 17, 2011. He was reunited with new Panthers head coach
Ron Rivera, a former Eagles assistant whom McDermott served alongside from 1999 to 2003. McDermott was
Pro Football Focus's second runner up to their Defensive Coordinator of the Year award in 2015. As the Panthers' defensive coordinator, McDermott led the team to finishes in the top ten in overall defense from 2012 to 2015. In the 2015 season, McDermott and the Panthers reached
Super Bowl 50, which was played on February 7, 2016. His defense only gave up one offensive touchdown in the game, but the Panthers lost to the
Denver Broncos by a score of 24–10.
Buffalo Bills 2017 season On January 11, 2017, McDermott was hired by the
Buffalo Bills as the 19th head coach in franchise history. On September 10, 2017, McDermott won his NFL head coaching debut in the season opening 21–12 victory over the
New York Jets, becoming just the third Bills head coach to win his first game with the team after
Marv Levy and
Rex Ryan. After a Week 2 loss to the
Carolina Panthers, also McDermott's first return to Charlotte since leaving the Panthers organization, McDermott would lead the Bills to four wins in the next five games, including a victory over the reigning NFC champion
Atlanta Falcons. However, they lost the next two games, including a 47–10 loss to the
New Orleans Saints, which prompted him to make the controversial decision to bench starting quarterback
Tyrod Taylor in favor of rookie backup
Nathan Peterman. Peterman played poorly against the
Los Angeles Chargers in his first career start, throwing five interceptions in the first half. He was benched for Taylor during the second half of the 54–24 loss, which dropped the Bills to 5–5. Despite the string of losses, the Bills then went on a 4–2 run to finish the season at 9–7, clinching the #6-seed in the AFC and their first playoff appearance in 18 years, thus ending both the NFL's and the North American professional sports franchise's longest active playoff droughts during McDermott's first year as head coach. The Bills would go on to lose to the
Jacksonville Jaguars 10–3 in the AFC Wild Card game.
2018 season In 2018, McDermott's Bills finished 6–10 and missed the playoffs, but had a strong finish to the season after a 2–7 start. After suffering blowout losses in four of the first nine games, partly caused by a lack of offensive talent, the Bills adjusted their roster, allowing them to stay competitive in each of the last seven games. Buffalo's defense improved in 2018. The 2018 season was McDermott's only losing season as a head coach.
2019 season McDermott was nominated for
NFL Head Coach of the Year for the 2019 season after leading the Bills to a 10–6 record, receiving their second playoff berth in three seasons as the #5-seed in the AFC. The Bills would lose 22–19 to the Houston Texans in overtime during the Wild Card Round despite a 16–0 third quarter lead.
2020 season On August 12, 2020, McDermott signed a contract extension through 2025. The 2020 season marked many instances of growth and success for McDermott and the Bills. Quarterback
Josh Allen developed dramatically, turning into an MVP candidate and leading the Bills to their first
AFC East Division Title since 1995, as well as a 13–3 record, tied for second best in the league with the
Green Bay Packers and behind the
Kansas City Chiefs. They also tied a franchise record for wins previously set in
1990 and
1991. After winning their first division title since 1995, they won their first playoff game in 25 years with a win against the Indianapolis Colts in the Wild Card Round, before defeating the Baltimore Ravens 17–3 for a trip to their first
AFC Championship Game in 27 years. In the AFC Championship, the Bills lost to the Kansas City Chiefs 38–24, ending their 2020 season, and ending the Bills' hopes of returning to the Super Bowl for the first time in
27 years. McDermott was questioned by fans and analysts for his play calling, with criticism specifically aimed at his decision making in regards to attempting field goals instead of touchdowns on a pair of fourth and goal situations. The Bills finished their 2020 season with a cumulative record of 15–4.
2021 season Prior to the 2021 season, the Bills increased protection for Allen by drafting offensive tackle
Spencer Brown from
Northern Iowa. After losing the season opener verus Pittsburgh 23–16, the Bills went on a four–game winning streak, including a 35–0 shutout against Miami and a 40–0 shutout over Houston. The Bills had a record of 5–1 within the division, with the sole loss to New England having taken place during particularly poor weather—wind gusts nearby were measured at over 55 miles per hour. Overall, the Bills would finish 11–6. In the AFC Wild Card game, they beat the Patriots 47–17 in a 'perfect' offensive performance, with each Buffalo possession ending in either a touchdown or kneeling to end the period. There was much anticipation going into the next round, as they would be once again be facing the Chiefs, led by
Patrick Mahomes. The game was hailed as one of the greatest modern NFL playoff games, with some commentators initially proclaiming it not only as the best playoff game in history, but one of the greatest games ever played, a
high-scoring shootout between Allen and Mahomes reaching its climax in the final two minutes of the fourth quarter, where a combined 25 points were scored. The Bills had emerged from the fracas with 13 seconds left in regulation and a 36–33 lead. However, Buffalo's defense would not hold, and Kansas City was able to score a field goal to tie the game 36–36 as time expired. The Chiefs then won the coin toss for possession to begin overtime, and ultimately scored a touchdown on the resulting drive to win the game 42–36. After the season, partially in reaction to this result—given Buffalo's offense was not given a chance to participate in the overtime period—the NFL changed their postseason rules to guarantee both teams a possession of the ball, even if the opening drive results in a touchdown.
2022 season In the 2022 season, McDermott led the Bills to a 13–3 record and a first-place finish in the AFC East. The Bills did not play 17 games in 2022 due to the
Damar Hamlin incident in Week 17, which McDermott got praise for helping cancel. The Bills won the
Wild Card Round against the
Miami Dolphins 34–31. The Bills' season ended in the
Divisional Round with a 27–10 loss to the
Cincinnati Bengals. Following
Leslie Frazier's resignation in February 2023, McDermott assumed play-calling duties on defense for the 2023 season. On June 23, 2023, the Bills announced McDermott's contract had been extended through the 2027 season.
2023 season As of the end of the 2023 season, McDermott became second on the Bills' all-time wins list, behind only
Marv Levy. In the 2023 season, McDermott led the team to an 11–6 record and an AFC East title. Following a
Wild Card Round win over the Pittsburgh Steelers, the Bills lost to the Chiefs 27–24 in the
Divisional Round.
2024 season In the 2024 season, McDermott led the Bills to a 13–4 record and another AFC East title. Following wins over the Denver Broncos in the
Wild Card Round and the Baltimore Ravens in the
Divisional Round, the Bills lost to the Kansas City Chiefs in the
AFC Championship.
2025 season In 2025, the Bills went 12–5, but it was not enough to win the division, seeding them as a wild card team. In the
Wild Card Round, the Bills beat the
Jacksonville Jaguars on the road, their first road playoff win in 33 years. The Bills lost in the
Divisional Round to the Broncos in overtime, after which McDermott criticized the referees for a pivotal play that was ruled an interception and ultimately led to the Bills losing. On January 19, 2026, it was announced that McDermott was fired after nine seasons with the Bills. Despite eight playoff appearances, and despite being perceived to have "overachieved" with a weaker roster in his final year, the Bills never reached the Super Bowl in McDermott's tenure with the team, with the Denver loss a major factor in Bills owner
Terry Pegula's decision to remove him. ==Coaching tree==