And even though France have defeated Wales on six occasions from the last seven attempts, the Toulouse speedster is taking nothing for granted against Warren Gatland's men.
"The Welsh team has had some great matches in this tournament," he said. "We must not rest on our laurels. The Welsh team has been very strong, although they have weaknesses, and we are looking to target those weaknesses.
"They have some very strong players, very dynamic. They are a real class act - we love playing against them."
Clerc added: "There is a huge amount of pressure in the knockout games. We know what it is like to be knocked out, and it made it all the more disappointing that we were eliminated in France last time. People will understand how motivated I am.
"As a squad we are very motivated. We know this could be the end for us, so it is an important moment. We have been given an opportunity, and we need to make the most of it."