After starting his career with South Shore and Imperial Hydro, Cardwell made his debut for Blackpool on 17 January 1931, in a 5–1 defeat at Middlesbrough.[3] It was his only league appearance of the 1930–31 season; he did, however, appear in the club's two FA Cup ties.[3] He missed the entire 1931–32 campaign due to injury and only returned with ten games of the following 1932–33 season remaining, appearing in six of them.[4]Sandy MacFarlane succeeded Harry Evans as Blackpool manager before the 1933–34 season, and the Scot only gave one start to Cardwell, in a 3–0 Boxing Day defeat at Hull City.[5] The following season, however, he selected him in 29 of the club's 42 league games.[6]
Cardwell served under his third Blackpool manager (this time Joe Smith) for the 1935–36 term, and he went on to be ever-present for the season. He also scored five goals. The first three came in consecutive games: against Bradford City on 7 March, Plymouth Argyle a week later, and then against Barnsley on 21 March. The remaining two were both from the penalty spot: against Hull City on 11 April and against Newcastle United on 22 April, in the penultimate game of the league campaign.[7]
Cardwell was also ever-present the following season, 1936–37, as Blackpool were promoted to the First Division as runners-up of the Second Division. In 1937–38, Cardwell started in eleven of the first twelve league games (and scored in one of them) before being sold to Manchester City. His final game for the "Seasiders" came on 16 October, a 2–0 defeat to Chelsea at Bloomfield Road.
Manchester City and beyond
Cardwell played 39 League games for Manchester City. The "Citizens" were relegated out of the top-flight in 1937–38, and finished fifth in the Second Division in 1938–39 – they were five points behind promoted Sheffield United.