Singh shot a three-under 69 to win the 84 Lumber Classic. He finished at 15-under-par 273, one stroke better than runnerup Stewart Cink.
This season has outstanding for Singh. He captured the PGA Championship and took over the No. 1 ranking in the world.
Singh held a two-shot lead over DiMarco to start fourth round.He wound up with his eighth victory of the season and a new single season earnings record.
"You're not really thinking about it when you're out there," said Singh, who won for the 23rd time on the PGA Tour.
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