D.D. Lewis was selected by the Dallas Cowboys in the sixth round of the 1968 NFL Draft. As a rookie at training camp, the team tried him at center, before moving him to outside linebacker.

In 1969, he spent what would have been his second season doing military service. In 1973 after serving as a backup for four seasons, Lewis took over the weakside linebacker position, when Chuck Howley retired, and held this position for eight straight years.

 

In the 1975 season NFC Championship Game, Lewis intercepted two passes in a 37-7 victory against Los Angeles Rams, helping the Cowboys become the first wild-card team to make it to the Super Bowl.

 

D.D. Lewis holds the Cowboys playoff record with 27 games played. During his NFL career, Lewis played in 12 NFC Divisional Contests, one NFC Wild Card Contest and nine NFC Championship Games. He made five Super Bowl appearances while winning Super Bowl VI and Super Bowl XII. During the 1980 season, he became along with Larry Cole, the first three-decade players in franchise history.