Diosdado Lozano was 20 years old at the time of these Summer Games and was making his Olympic debut. His only event was the men's 1500 metres, and on 9 August he was assigned to run in the second round's sixth heat. The top three in a heat, plus the next five overall fastest athletes advanced to the quarterfinals. Lozano finished his heat in a time of four minutes and 34.71 seconds and was eliminated from further contention as it placed him tenth and last of all the finishing runners.