He played three years at end for
St. Mary's College in
California beginning in 1932 under head coach
Slip Madigan. Erdelatz suffered a scraped leg that led to infection (and possible amputation) but failed to keep him off the field. He also had a
shoulder separation and twisted his knee, but again the injuries failed to keep him from playing. In 1936, Erdelatz became St. Mary's line coach under Madigan, then left St. Mary's for a similar position with the
University of San Francisco two years later. In 1940, he returned to St. Mary's for another two-year stint that was followed by service in the U.S. Navy during World War II. Erdelatz rose to the rank of lieutenant commander in 1945 and began the first of three years as a Navy assistant coach at the academy in
Annapolis, Maryland. During this time, he helped develop end
Dick Duden into an All-America. Looking to return to California, Erdelatz accepted the defensive coordinator's position with the
San Francisco 49ers of the
All-America Football Conference in 1948. Two years later, he returned to Navy to take over a football program that had won just four games over the previous five seasons. The stress of rebuilding the program took its toll. The first year as Navy's head coach, Erdeletz lost 50 pounds to drop to 195. In 1950, Erdelatz led an upset of arch-rival Army. The Black Knights entered the game with an 8–0 record which had not lost in 28 contests. Army also had defeated Navy five times in the last six games. Although Navy had only a 2–6 record, an outstanding defensive effort resulted in a 14–2 victory for the Midshipmen. After two years at Navy, Erdelatz's record stood at 5–12–1, but he would never again have a losing season in his final seven seasons and would finish 5–3–1 in his games against Army. In 1954, the team finished 8–2, losing close games to Pittsburgh and Notre Dame. Erdelatz labeled this squad, "A Team Called Desire" and then went on to shut out the
University of Mississippi in the 1955 Sugar Bowl. Three years later, the Midshipmen competed in the
Cotton Bowl Classic, where they knocked off
Rice University, 20–7. The latter win came one year after Navy's bid to play in a bowl game was rejected despite having only one loss. In 1956, Erdelatz hired
Steve Belichick to be an assistant coach and scout, a position Belichick held until 1989. After the bowl victory over Rice, Erdelatz was courted by other schools and nearly accepted the task of replacing
Bear Bryant at
Texas A&M University. After the 1958 season, he was also seen as a candidate for the 49ers' head coaching job, but began spring practice the following year at Navy. On April 8, 1959, Erdelatz resigned as head coach of the Midshipmen, citing a number of factors, including the desire for an easier schedule. ==Professional football==