Kelsey's professional career began with stage appearances in her home of Minneapolis, Minnesota, with her good looks and striking mane of red hair winning her success that ultimately landed her in Los Angeles in 1972, with appearances in small roles on television shows like Emergency! and The Rookies, and the television movie The Picture of Dorian Gray (1973). Her first recognition came with an appearance on an episode of The Mary Tyler Moore Show as a rival to Sue Ann Nivens (played by Betty White), where she met Ed Asner on the set, with whom she later worked on the spin-off show Lou Grant. Her appearance on The Mary Tyler Moore Show led to prominent guest appearance on shows like M*A*S*H, The Streets of San Francisco, Barnaby Jones, Spencer's Pilots, Quincy M.E., The Rockford Files, the television films The Last of Mrs. Lincoln (1976) Something for Joey (1977), and Eleanor and Franklin (1976), Eleanor and Franklin: The White House Years (1977), and the miniseries Captains and the Kings (1976). She also appeared in the episode "The Mask of Adonis" from the 1977 series Quinn Martin's Tales of the Unexpected (known in the United Kingdom as Twist in the Tale).