during his career alim-ud-din played 140 first-class matches and scored 7,275 runs, with the average of 32.77, including 14 centuries and 38 fifties; he also took 40 wickets. critics considered him to be an excellent fielder. he made his debut for rajasthan aged only 12 years 73 days, becoming the youngest player to have played first-class cricket. in 1942–43, he played his maiden match in the ranji trophy, scoring 13 and 27 runs in his two innings. his highest score in first-class cricket was 142, against worcestershire in 1954. domestically, alim-ud-din represented sindh, rajasthan, karachi, bahawalpur and gujarat, and became the first pakistani batsman to face a ball bowled by an international bowler on pakistani soil, in a match between the sindh and west indians in 1948. during pakistan's 1954 tour of england, alim-ud-din scored more than 700 runs, including two centuries in the first two matches. he was most successful during 1961–62, scoring 1,020 runs in 12 matches at an average of 51.00. in the same season he captained karachi, leading the team to victories in the quaid-e-azam trophy and ayub zonal trophy. his final season in first-class cricket was 1967–68.