Clarence Darnell Gilyard, Jr. (born December 24, 1955) is a former American actor and current college professor who has featured in movies and television since 1980, who's known for his character-type roles. He is sometimes credited as Clarence A. Gilyard. Gilyard is best known for his roles as Andy Griffith's second private investigator and right-hand man, Conrad McMasters, on the popular 1980s legal drama series, Matlock (a role he played from 1989 to 1993), and as Chuck Norris's partner and best friend, Texas Ranger, James "Jimmy" Trivette, on the popular 1990s crime drama, Walker, Texas Ranger. In the 2000s, he also played Rev. Bruce Barnes in two of the three Left Behind: The Movie films.