At 16-under-par 200, the native of Argentina is two better than Andrew Marshall () and overnight leader Warren Bennett (), while Ignacio Garrido () and Henrik Bjornstad share joint fourth at 13-under.
Meanwhile, local products Jean Van de Velde and Thomas Levet both ended at 12-under following the third round in France.
Leader Berendt is looking to become the third winner from Argentina this year on the European Tour.
Angel Cabrera took the Argentina Open earlier in the season, while Ricardo Gonzalez was victorious not long ago at the European Masters.
Berendt ' a good friend of Gonzalez ' is vying to join his countrymen.
Now I hope I can be the next winner from Argentina, he said confidently after his round.
If his play on Sunday mirrors that of Day 3, he may have a better-than-average chance.
Berendt collected three birdies over his opening nine holes and then added two more red numbers at the par-4 13th and par-5 16th for a bogey-free 67.
Lying 111th on the current money list, his immediate goal is to end within the top-116 and retain his playing privileges next season.
Of his chances, the 37-year-old said: It would be great to winbut if it doesnt happen this week, then I want to make sure I have plenty of weeks next year to try and win.
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