Thomas sealed his first victory of the 2017-18 season when he birdied the second playoff hole and Leishman had made bogey after finding the water.

The pair went to a sudden-death playoff after completing the first US PGA Tour regular-season event in South Korea tied at 9-under 279.

Cameron Smith of Australia finished one stroke back in third place at 8-under, with Whee Kim, the highest-placed finisher of the 16 South Korean players in the field, finishing fourth at 7-under after closing with a 72.

Thomas won five times during the 2016-17 season, including his first Major at the 99th PGA Championship, which he won in August.

South Africa’s Branden Grace finished in a tie for 15th after rounds of 72, 67, 74 and 72 for a three-under total of 285. Charl Schwartzel closed with a level-par 72 after opening rounds of 71, 72 and 75 to end tied for 28th position on two-over 290.

Tour Championship winner Xander Schaueffele had a tournament to forget. The young American had started with a three-under 69 opening round, but dropped like a stone after that, with rounds of 82, 78 and 76 for a 17-over-par total of 305.

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