The South Korean finished on 17 under par in Florida to take the $468,000 (�300,000) first prize and record his second tournament victory of the season.

Glen Day was second after a closing 69 and Mark Brooks shot 67 to finish one shot further back on nine under.

Choi was 31st on the tour money list when the 30 entrants for this weekend's World Golf Championship were selected.

His seven-shot victory margin is the season's largest, bettering Vijay Singh's win at the Shell Houston Open by one shot.

"When I first started out the day I did feel some pressure and uneasiness, said Choi.

"But as the holes went by I felt much more comfortable. I just said to myself 'I'll just take it hole by hole'."

Choi won the Compaq Classic of New Orleans earlier in the year to take his first PGA Tour title.

After a course record 63 in the first round, Choi took a five-shot lead over Pat Perez into the final round.

Perez shot 74 to finish 11 back.

Day, who trailed by six at the start, closed to within three shots after making his fourth birdie of the day at the ninth hole, but that was as close as he got.

"I said 12 under [would win] at the first of the week. Obviously, I was wrong. K J played really well," said Day.

Teenager Ty Tryon, who drew the week's largest galleries as he returned for his first tournament since March, closed with a four-over 75 to finish one over.