Garrett was one of the longest-tenured coaches in the NFL until his contract was not renewed after the 2019 season.
The 53-year-old first took over the Cowboys on an interim basis in 2010 and led the squad to an 85-67 record during his time at the helm, winning the league's Coach of the Year award in 2016 thanks to a 13-3 record. He had only one losing season in his time with the team.
On the other hand, he went just 2-3 in the playoffs and never got the team past the divisional round, extending a conference title game drought for the Cowboys that dates back to 1995.
The team entered 2019 with high expectations but only managed an 8-8 finish while missing the playoffs.
Dallas has replaced Garrett with Mike McCarthy.
Despite his problems over the past year, Garrett had as good a resume as anyone on the market with a proven record of success at the NFL level. With 15 years in the coaching ranks and eight years in the league as a player, he has more than enough experience to be successful at this level.
Garrett has especially proved himself on the offensive side of the ball with seven top-10 offenses in 13 years in Dallas as a coach and offensive coordinator. The 2019 team finished No. 1 in the league in total yards and sixth in points.
Now he will move within the division and head back to the NFC East rival Giants.
Garrett played in New York from 2000-2003 and served as the team's backup quarterback during the team's NFC-winning campaign in his first season there. This time, he will attempt to turn around an offense that ranked 18th in the NFL in points and 23rd in yards last season.
Quarterback Daniel Jones showed promise in his first year but will hope to improve in 2020 alongside Saquon Barkley, Sterling Shepard, Evan Engram and more. If the players can stay healthy, there is enough talent to make this a top-10 unit.
Garrett's coaching experience will also make him a valuable resource for Judge, who is making the jump from wide receivers coach and special teams coordinator.