Nitties started the final round just two behind the leaders David Lingmerth and Scott Harrington and was still in touch with the leaders with just nine holes to play but he was unable to make any real progress over the closing stages.
Aron Price was the next best Australian in a share of 12th position.
The tournament was won by American Scott Wilson who defeated Scott Harrington in a playoff.
Wilson had made just US$6,500 in tens starts on this year's tour prior to the US$111,000 he earned today. Wilson moves from 165th to 23rd on the money list.
Only one Australian, Cameron Percy (10th), is now inside the all important top 25 on the money list.
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