On July 3, 1943, Handler took over the Cardinals' head coaching duties when head coach Jimmy Conzelman accepted a front office position with baseball's St. Louis Browns. However, with manning shortages due to World War II, the Cardinals lost all 10 games that season. The team then merged with the Pittsburgh Steelers in 1944 to form what was referred to as "Card-Pitt" in the standings. Handler and Walt Kiesling were named the team's co-coaches. That effort also resulted in a winless season in 1944, and after a 1–9 season the next year, Handler gave way for the returning Conzelman.