Frost attended Franklin High School, before accepting a football scholarship from the University of Tennessee.
[2][3] Frost was signed as an undrafted free agent by the Dallas Cowboys after the 1961 NFL draft, which at the time was seen as a coup, as his skills were being compared to those of first round draft choice Bob Lilly.
[4] He became a starter at defensive tackle in his second season,[5] but suffered torn ligaments in his right knee during the third game against the Los Angeles Rams and was lost for the year.
On May 13, 1963, he was traded to the Cleveland Browns in exchange for a third round draft choice (#39-Roger Pillath).
[8] In 1963, he sued the Dallas Cowboys because of the medical treatment he received for his injured knee.