The 72-year-old, Arsene Wenger, sold over 500 players during his 22-year stint with the Gunners.
Anelka arrived in England as an unknown 17-year-old and left for Real Madrid as the most exciting young striker in European football.
Before he left, the Frenchman led Arsenal’s attack during the second half of the 1997/1998 season in the absence of Ian Wright and won the PFA Young Player of the Year award.
Arsenal made a staggering £22.5 million profit on Anelka who had cost just £500,000 from Monaco and bought Thierry Henry with the proceeds.
Anelka failed to shine in Madrid and endured a nomadic career that saw him represent over a dozen clubs, including five more in England alone.
As Arsenal fell behind their rivals, meanwhile, Wenger was forced to sell the likes of Robin van Persie and Cesc Fabregas who, like Anelka, he had helped turn into superstars, but the sale of his compatriot still represents his biggest regret.
Speaking at an event alongside his friend and former colleague David Dein, Wenger said: “Yes, we used the Arsene Wenger card and players wanted to go to where they would win.
“My biggest regret and shame is that Anelka left. He could have been special, instead, he played for 13 clubs,” he said.