Youzhny, ranked 17th in the ATP Race, is one of 18 players fighting for the two remaining spots for the Nov. 11-18 season-finale in Shanghai which features the world's top eight.
Clement fought back from a break down in the first set but showed signs of nerves throughout and eventually bowed out with a double fault on match point.
Earlier, American Mardy Fish fired 19 aces to knock out Dmitry Tursunov 7-6, 6-4, his third victory in as many encounters with the Russian.
Each of the world's top 20 except number five Andy Roddick have entered the indoor event in Paris.
The seeds have a first-round bye and will not appear at the Bercy hall before Tuesday.