In football, he shifted to playing wide receiver, where he was a four-year starter, although he never led the team in receptions.

In January 2020, he was elected as one of 10 seniors to the Centennial Slate for the Class of 2020 of the NFL Pro Football Hall of Fame.

In 1973, he had a breakout year with the arrival of head coach Mike McCormack, leading the league with 67 receptions for 1,116 yards (16.7-yard average) and was tied for fourth with nine receiving touchdowns.

In 1977, Ron Jaworski was named the starting quarterback, with Carmichael leading the team with 46 receptions for 665 yards and seven touchdowns.

On August 8, he was signed as a free agent by the New York Jets, who were looking to improve their depth at wide receiver while Wesley Walker held out in a contract dispute and Lam Jones recovered from a broken collarbone.

[5] On September 6, he signed with the Dallas Cowboys, who were looking for wide receiver depth after Tony Hill was injured in the season opener 20–13 win against the Los Angeles Rams.

He holds the Eagles record for most games with a touchdown for both the regular season (69) and playoffs (five, shared with Duce Staley and Brian Westbrook).

[9] Carmichael was selected to the NFL 1970s All-Decade Team by voters of the Pro Football Hall of Fame.

[11] After retiring from his playing career, he settled in South Jersey and joined a Philadelphia travel agency as a vice president for sales.