In February 1949, Close underwent a medical examination with the British Army, but due to an injury he had suffered playing football his call-up was delayed by a few months, allowing him to continue into pre-season training with Yorkshire. His performance in pre-season was such that he was given a trial for the county in the two first-class matches against Cambridge and Oxford Universities. He made his debut on 11 May 1949, alongside Fred Trueman and Frank Lowson – all three went on to play for England. Close impressed the Yorkshire hierarchy enough for his trial to be extended into the County Championship season; Bill Bowes, one of Yorkshire's coaches, declared that he was the "natural successor to the veteran all-rounder Frank Smailes". Close continued to perform well, particularly his bowling; in his fifth first-class game, against Essex, Close took five for 58 in Essex's first innings, then top-scored with an undefeated 88 runs in the Yorkshire innings. His performances for Yorkshire earned him a place in the North v South match, which was also being used as a trial for selection for the upcoming Test matches against New Zealand. Close scored two runs, and did not take a wicket; "The Times" described his batting as a "disappointing feature" of the match, but noted that despite not taking any wickets, "he bowled his off-breaks round the wicket well enough."