Dr. Knickerbocker joined the faculty of the university’s English Department in 1946. In addition to teaching and directing research, he served as associate dean of the College of Liberal Arts (1957–58), dean of the College of Liberal Arts (1958–63), head of the Department of English (1963–71), and vice president for academic affairs of the UT system from 1971 to 1973. He retired from the university in 1974.
He was an internationally renowned specialist in nineteenth-century English literature, known especially as editor of New Letters of Robert Browning (1950) and the Modern Library edition of Robert Browning (2nd ed., 1961). He was also the author of several successful textbooks and of numerous articles in scholarly journals. His intellectual contributions to the life of the university have been recognized by placement of a plaque in his honor on a faculty study.