He played college football for the Penn State Nittany Lions, twice earning consensus All-American honors.
An all-around athlete, Onkotz helped earn Penn State the nickname "Linebacker U," as the first great linebacker in the school tradition; but thanks to his speed he also held the unlikely position of punt returner, with an impressive average of over 13 yards per return.
[10] Onkotz amassed 287 tackles, which at one time ranked third on the Lions' career list (but as of 2024 is just outside of the top five[10]).
Onkotz made the 1969 Academic All-America team and was also selected to play in the 1970 Hula Bowl.
[15] The severely broken leg effectively ended his professional career after just nine games played.
[11][16] Onkotz was traded to the Pittsburgh Steelers, and after a year attempted a comeback, but did not make the team.
[15][17] After his short professional career, Onkotz attended graduate school at Penn State.