The much-travelled French striker, 28, today joined Chelsea in a £15million deal from Bolton.

Wenger had not been in the Arsenal job long when he forked out £500,000 for the then Paris Saint-Germain youth player during November 1996.

An injury to Ian Wright gave Anelka his chance and his goals helped the Gunners completed the double in 1997/98, scoring in the FA Cup final win over Newcastle.

However, the young forward soon became unsettled amid rumours of excessive wage demands and temper tantrums and eventually Wenger reluctantly sold him to Real Madrid in the summer of 1999 for £22.3million after he scored 28 goals in 90 matches.

Although Anelka played in the Champions League final win over Valencia, he never settled and went on to have a spell at PSG again, as well as more stints in England at Liverpool, Manchester City and then Bolton, via Fenerbahce.

Speculation was rife Wenger would move for a player he still rates highly last summer after the departure of Thierry Henry to Barcelona.

The Arsenal manager still wonders what might have been had Anelka stayed.

Wenger said: "It is my biggest regret that he moved at that time because I felt he was a star here.

"When he left he was a regular member in the French squad. He moved to Real Madrid, Thierry Henry moved here. Thierry played in the [2000] European Championships - and Nicolas did not.

"I still believe at that time it was a big mistake, that move."

Wenger admitted he had thought about trying to bring Anelka back "at some stage".

He said: "When Henry wanted to leave you always consider if you are strong enough. I decided to go with [Nicklas] Bendtner and then I signed Eduardo - but you consider all the strikers available.

"I am glad Nicolas has gone to a top club because when you are a football manager and you love football you do not want talent to be spoilt and you want the best players to be at the best level.

"Justice in the game is that the best player is the best and that is where Nicolas belongs."