He played college football for the Louisiana Tech Bulldogs and was selected by the Cleveland Browns in the fourth round of the 2004 NFL draft.

He set an NCAA single-game freshman record by throwing the ball 72 times in the 42–31 loss against the University of Miami.

A 39–36 win over Oklahoma State University, which came down to a 36-yard touchdown pass on a fourth-down-and-10 with 60 seconds in the opener of his junior season.

He started 42 out of 43 games of his college career, establishing school records for completions (1,088), attempts (1,827) and passing yards (12,994).

[2] He still holds several NCAA Division I FBS records:[3] In 2017, he was inducted into the Louisiana Tech Athletics Hall of Fame.

On April 24, 2005, he was traded to the Tampa Bay Buccaneers in exchange for sixth round 2005 draft pick (#203-Andrew Hoffman).

In 2007, he appeared in five games with three starts, registering 1,009 passing yards, three interceptions, five touchdowns and a 91.7 quarterback rating.

In week 13, McCown produced his finest performance as an NFL quarterback, throwing for 313 yards and two touchdowns during an emergency start for the injured Jeff Garcia in the Buccaneers 27–23 victory over the New Orleans Saints.

On September 5, 2009, McCown was traded to the Jacksonville Jaguars in exchange for a seventh round 2010 draft pick.

[8] He made his first start as a Jaguar in the season opener against the Tennessee Titans, completing 17 of 24 passes for 175 yards.

On September 18, McCown was benched in favor of Blaine Gabbert, after posting the lowest passer rating (1.8) for a starting quarterback in club history.

[12] After solid performances in preseason games, McCown was selected to serve as the primary backup to Saints starting quarterback Drew Brees.

On November 5, McCown underwent successful lower-back surgery, effectively ending his season after he was placed on injured reserve.

[20] He was signed to help the team get through training camp and the preseason, after losing fourth-string backup Zac Dysert, who suffered a season and career ending back injury.