Smith racked up 8,278 points in the decathlon to outscore runnerup Yordan Garcia of Cuba by 165 points. Competing for Jamaica, he led by nine points after the first day of competition that included five events.
On Tuesday, Smith ran a time of 14.06 in the 110 hurdles to build his lead and then built a 324-point margin by having the best discus throw of any of the competitors with a toss of 53.24 meters. He went 4.40 meters in the pole vault, threw the javelin 50.23 meters and finished with a time of 4:40.12 in the 1500 meters to wrap up the victory.
Former Tiger Vonette Dixon reached the finals of the women's 100 hurdles on Tuesday with a time of 12.86 and will run in the finals on Wednesday.
Another former Tiger, Olympian Avard Moncur, qualified third in the 400 meters with a time of 45.27.