The Busan-born 20-year-old midfielder, who had been mostly used off the bench by incoming Valenciennes boss Daniel Sanchez this term, was a 63rd-minute substitute in the draw.
Valenciennes president Jean-Raymond Legrand revealed the move last week before the formalities were completed in time for Sunday's match.
"An agreement was signed. He left Monday morning for a medical visit and everything should be finalised by the end of the week," Legrand told AFP.
Nam has agreed to a two-and-a-half-year deal with the Qatari champions who currently lead the Stars League and will compete in the 2012 AFC Champions League.
The move sees Nam link up with ex-Valenciennes team-mate Djamel Belmadi who is the current coach of Lekhwiya.
Nam's agent Kim Dong-Gook explained the move when he told JoongAng Daily: “Tae-Hee is not playing as a regular member for Valenciennes. Since he is not playing enough, he is worried about his physical fitness as well.”
The 20-year-old, who has made seven senior appearances for his country, is seen as a replacement for Iraq international Nashat Akram who was recently released.
What do you think; Is Nam Tae-Hee's move to Qatar good for his national team prospects?
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