Selby was tapped to co-star as the husband of Barbra Streisand in the underrated "Up the Sandbox" (1972) and had a shot at stardom teamed with Ron Leibman in the well-made "The Super Cops" (1973). He deliberately stayed away from TV for a spell because he had become so identified with the role of Quentin Collins, but when he did finally make his first primetime appearance, it was a memorable one. Selby played an art teacher romantically drawn to Olivia Walton (Michael Learned) in a 1974 episode of "The Waltons" and had the distinction of being the only actor (other than the series regulars) to kiss Learned. Shots at Broadway stardom opposite Jane Alexander in "The Heiress" (1974) and Betsy Palmer in Tennessee Williams' "Eccentricities of a Nightingale" (1976) didn't pan out.

Selby found success in primetime, first with the miniseries "Washington: Behind Closed Doors" (ABC, 1977), loosely inspired by the Watergate crisis. He was the mysterious Michael Tyrone on the NBC primetime serial "Flamingo Road" (1981-82) before he joined CBS' "Falcon Crest". For eight seasons (1982-90), Selby played the ruthless yet charming businessman Richard Channing who often did battle with Jane Wyman's matriarch. He got a chance to fulfill a dream by portraying the father of the modern Olympics in "King of the Olympics: The Lives and Loves of Avery Brundage" (syndicated, 1988). As he aged, with his dark hair turning silver, Selby was often cast as stern fathers as in "Dying Young" (1991) and "White Squall" (1996). A change of pace role was his turn as a lawyer with decidedly kinky sexual tastes who becomes a hostage in the independent film "Headless Body in Topless Bar" (1995). More recently, Selby played the intelligence operative in charge of a covert operation involving mercenaries in the syndicated series "Soldier of Fortune Inc./S.O.F.: Special Ops Force" (1997-99).