The 23-year-old had only been at Emirates Stadium since August following his switch from Chelsea where the midfielder had become frustrated at a perceived lack of first-team opportunities.

However, after 13 appearances for the Gunners, he decided another move was necessary to push his claim for a place in the France squad at Euro 2008 and secured a transfer to Portsmouth, where he would go on to win the FA Cup final at Wembley.

Wenger, though, is in no doubt had the young midfielder shown more "patience", the opportunities would have come his way with the Gunners, especially following the departure of Mathieu Flamini to AC Milan.

"I came to the conclusion that Diarra could not cope with the fact that he was behind the other players here in midfield," said the Gunners boss.

"I thought the best option was to let him go because I already had Denilson, [Abou] Diaby and Gilberto all trying to get into the team as well. It was a congestion."

Wenger told the June edition of the official Arsenal magazine: "I bought Diarra in the summer because I thought Flamini might leave at the end of the season and if he was able to be patient, he would get his chance.

"It turned out he wasn't capable of that. With Euro 2008 in mind, he panicked.

"I did explain when he joined that he might have to be patient, and he acknowledged it, but he couldn't cope with the situation, and also did not want to go on loan anywhere either."

Wenger insisted his decision not to bolster the squad during January was a sound one, given the position his team were then in, standing two points clear of Manchester United at the top of the Barclays Premier League after the final matches of 2007.

However, the Arsenal manager could not envisage the way the season would quickly unravel following injury to key men Eduardo da Silva, Tomas Rosicky and Robin van Persie while main marksman Emmanuel Adebayor suddenly hit a goal drought.

"The transfer window was open, but at the time I didn't feel we were in need of any more players," reflected Wenger, whose young squad would eventually finish third and exit the Champions League in the quarter-finals to Liverpool.

"We had [Theo] Walcott and [Nicklas] Bendtner making big strides forward, and Eduardo was on form then and Adebayor on top form too. Overall when he is on fire, he scores in every game.

"I thought van Persie would be back shortly, and also did not expect to lose Rosicky for so long either."

Wenger maintained: "You have to keep the balance right between having competition in the squad, and having too many players. The squad did not look light at any time."

Just what shape Arsenal will be in for the start of next season remains to be seen.

With Flamini already gone, speculation continues that winger Alexander Hleb will soon follow him out of Emirates Stadium, with Real Madrid and Inter said to be leading the chase.

Meanwhile, reports in Italy claim Roma are ready to move for veteran Brazilian Gilberto, who saw his impact limited last season and is entering the final 12 months of his existing deal.

His compatriot Robinho, at Read Madrid, could be one potential target for Wenger, who is awaiting an answer on the club's move for Samir Nasri as the Marseille playmaker weighs up his options while Cameroon international midfielder Jean II Makoun is said to be ready to quit Lille for the chance to play in England, with Emirates his preferred destination.

Arsenal, though, look set to continue to invest in youth.

A deal for France Under-17 international Francis Coquelin is expected to be concluded before the European Championships, while Cardiff's highly-rated teenager Aaron Ramsey is said to be another on Wenger's radar.

ends