[4][3][5] He played college football at Ohio State University under coach Sam Willaman, forming the basis of his offense.

He played piano in small bands during his college years to make extra money (including one called the Red Hot Peppers).

[3] Gillman's innovations in passing offense are often praised as the foundation of modern football, but "Perhaps his most lasting legacy was his use of film to study players and formations...."[8] Always deeply interested in the game, while working as one of his family's movie theater ushers, he removed football segments from newsreels the theater would show, so that he could take them home and study them on a projector he had bought.

[10] His participation in the inaugural Chicago College All-Star Game caused him to arrive late for Redskins training camp, and he would fail to make the team.

[4][14] Schmidt's number of plays and formations far exceeded his contemporaries, and he instituted a wide-open high scoring offense, extremely unusual for the 1930s (outside of the Southwest Conference), which also was a boon to the school growing its attendance during the Great Depression.

[1][13][15] While at Army he befriended future hall of fame coaching great Vince Lombardi, with whom he discussed football strategy.

Lombardi would use Gillman's blocking scheme to great effect as coach of the Green Bay Packers' championship teams.

[13][15] Among his players was Ara Parseghian, a future College Football Hall of Fame coach at Miami, Northwestern and Notre Dame.

[16] After a year at Army under Blaik, Gillman became head coach at the University of Cincinnati from 1949 to 1954, with a record of 50–13–1, three Mid-American Conference championships, and two bowl games; while making full use of situational substitution.

[18] At the time he left Cincinnati, it was written that Gillman had a forceful, confident and determined personality; was impatient with mistakes, the hardest working coach, a perfectionist, aimed to succeed at the highest level; and could run up the score like Schmidt.

[5] He became a professional head coach for the first time with the Los Angeles Rams in 1955, after the team had declined in wins the previous two seasons (8–3–1 in 1953 and 6–5–1 in 1954).

A trade for Jim Cason with the San Francisco 49ers also proved helpful in the rookie season that saw Gillman's coaching described as "red-meat, un-finessed brand of football" on the way to a record of 8–3–1 that narrowly beat the Chicago Bears for the right to play for the 1955 NFL Championship Game (their fourth appearance in the past five seasons) against the defending league champion Cleveland Browns, appearing in their sixth straight NFL Championship Game.

Playing at home in the Los Angeles Memorial Coliseum due to the rotation of the time, the Browns never trailed while forcing six Van Brocklin interceptions on their way to a 38–14 victory.

[citation needed] It was with the Chargers that Gillman developed the innovative aggressive downfield passing attack for which he would become known, and which would change football.

"[19] Hall of Fame coach Bill Walsh, who is usually identified with developing the West Coast Offense, stated much of what he did derived from Gillman.

[28] "Sid Gillman brought class to the AFL," Oakland Raiders managing general partner Al Davis once said of the man he served under on that first Chargers team.

[35][36] On the other hand, Chargers receiver and tight end Dave Kocourek (1960-65) found Gillman a people person who was not given proper credit for his interpersonal skills.

When Faison was traded in 1966, Gillman called the former four-time All-AFL defensive end one who "has a long way to go to become average, much less outstanding.

The 1960 and 1961 teams were led by future Hall of Fame player Jack Kemp (1960-61) at quarterback to go with Paul Lowe (1960-61) and Keith Lincoln (1961) as running backs.

[48][49] In 1962, with injuries to Kemp and rookie future Hall of Fame receiver Lance Alworth, the Chargers had their only losing season in their AFL tenure (4–10).

[50][20] Even worse for Gillman, he put Kemp on waivers on a Saturday before a game to open up a roster spot, with the common custom being that no other team would claim a player when so waived.

[56] In addition to Lincoln, Alworth, Kemp, Lowe, Ladd, Faison and Hadl on Gillman's teams through the '60s, Gillman also coached such notable players as future hall of fame offensive tackle Ron Mix,[58] Speedy Duncan,[59] Kenny Graham,[60] Dick Westmoreland,[61] and Frank Buncom.

[63] Gillman and Al Davis (also Jewish), emphasized recruiting from Historically Black Colleges and Universities (HBCU), and Gillman instituted a training camp policy that players would room together based on position so that black and white players would room together, a rarity in the early 1960s.

[67] After a fifth straight loss to start the season, Gillman took over as coach by firing Peterson, which saw them win once the rest of the way.

[71] Midway through the season, Gillman and the Oilers acquired future Hall of Fame defensive tackle Curley Culp[72] and a first-round draft choice in 1975 from the Kansas City Chiefs for John Matuszak (each player had threatened to jump to the World Football League).

[78] The Bears, with Walter Payton leading the way in rushing yards (1,852), won 9 games and earned their first postseason appearance in 14 years, which ended in a loss in the Divisional Round.

[80] Gillman taught Jaworski and future Hall of Fame receiver Harold Carmichael their signature "meet me at the corner" play.

[83] Gillman agreed to serve as director of operations and signed quarterback Doug Williams, who later led the Washington Redskins to victory in Super Bowl XXII.

[84][85] Although Gillman signed a roster of players to play for the Tulsa, Oklahoma-based franchise, he was fired by Tatham six months later in a dispute over finances.

[86] Gillman then served as a consultant for the USFL's Los Angeles Express in 1984, where John Hadl was the coach and future Hall of Famer Steve Young was the quarterback.