Berendt ended at 20-under-par 268, one stroke better than Van de Velde, who fired a 65 to end in outright second.
Meanwhile, another Frenchman Thomas Levet finished in a tie for third with Santiago Luna and Andrew Marshall at 16-under.
With his victory, Berendt becomes the third Argentinian winner this year on the European Tour. He joins Angel Cabrera and Ricardo Gonzalez as champions in 2001, and moves from 111th to 77th on the Volvo Order of Merit in addition to securing a two-year exemption.
This is absolutely fantastic, exclaimed Berendt following the round. I cant put it into words what this means to me. I was so nervous over the last few holes but I was proud of the way I handled myself, and my game, and came through to win.
Indeed, Berendt handled himself beautifully all week, never moreso than on Sunday.
Three birdies over his opening nine holes kept his lead secure, and Berendt added one more red number at the 12th for a fine 68. No bogies were to be had.
To now be thought of in the same breath as the other great Argentinian golfers who have won in Europe is absolutely unbelievable, said Berendt.
For Van de Velde, had it not been for a lone bogey at that same par-4 12th, he might have made it into a playoff, as he rattled in six birdies and an eagle for 65.
However, the week was a success overall, as he moved to 106th on the Order of Merit list and secured his playing privileges for next year.
It could have easily been three or four shots better but I am happy because now I have a job next year, stated Van de Velde.
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