 Coldwell signed for Sheffield United in September 1951 from local side Norton Woodseats for a fee of £100, before finally making his debut against Southampton in April 1952.Although a late developer, Coldwell formed a splendid full-back partnership with first Cliff Mason and then Graham Shaw, playing in 410 league games for the Blades which included two rare goals.The captain of the 1961 promotion team, he was retained as a player until 1968, although by then he was fully employed as a junior coach.