Mesut Ozil has been warned he will trade in the opportunity to be the main man at Arsenal if he joins Barcelona in the January transfer window.

Speculation is rife that the ex-Real Madrid playmaker is being lined up by the Catalan giants as a cut-price alternative to Liverpool's Philippe Coutinho.

Ozil is out of contract at the end of the season and would be available on a free, but with Arsenal manager Arsene Wenger trying to prevent him moving to Manchester United he is reportedly open to allowing the player to leave in January.

Former Gunners defender Martin Keown says Ozil – who produced his best display in an Arsenal shirt for many years in the north London derby defeat of Tottenham Hotspur last weekend – will have to cope not being the centre of attention should he move.

"I don't think he would be a bad signing," the title-winning defender told the Daily Mail. "Everyone knows his calibre. Look at who he would be assisting – Lionel Messi, Luis Suarez... they are not going to turn him down because they know his vision.

"But the next step for him was to become a Messi- or a [Cristiano] Ronaldo-type player – more ruthless. Going to a situation like that at Barcelona admits he is a provider rather than someone who can be a number one.

"Most of the time he looks like he is playing for fun. When he's happy, he plays well. But when he's not happy, he doesn't."

AS understand Ozil has told Barcelona he wants €19m-a-year [£17m] to move to the Nou Camp in the winter window, and is also demanding a signing on fee.

The publication understands that the deal hinges on whether Ernesto Valverde's side can offload midfielder Arda Tura in January, with the Turkey international currently the sixth highest earner at the club.

Catalunya Radio meanwhile claim that Ozil's agent Dr Erkut Sogut has already held talks with Barcelona and that a three-and-a-half-year deal is on the table.

Despite the deal seemingly being on the brink of completion, Sport understand Barcelona are still yet to be convinced Ozil represents a worthwhile investment, with the total deal set to cost in excess of €79.5m (£70m).

Reports suggest the five-time Champions League winners will pay Arsenal €22.5m to acquire Ozil six months ahead of him being available for nothing.

Barcelona's fingers have already been burned once in the deal that brought Turan to the club from Atletico Madrid in a move initially agreed in July 2015, prior to his arrival in January.

Turan's big wages and poor performances have made him difficult to sell on, and some Barcelona officials are concerned Ozil's career could go the same way after his indifferent spell with Arsenal in the Premier League.

There are also worries that his wage demands could create hostility in the Barcelona dressing room, with his pay-packet similar to that earned by lead striker Luis Suarez.

In addition, there are also concerns over Ozil's physical robustness, with the ex-Wolfsburg man having missed 38 games across four-and-a-half seasons at Arsenal due to various fitness concerns.

Mesut Ozil
Ozil is seemingly on the brink of leaving Arsenal in January. Getty Images