Wenger faces fight to keep Arsenal's troubled trio

Portsmouth have emerged as the favourites to sign Lassana Diarra from Arsenal in the January transfer window although they will face strong competition from other Premier League clubs.

It means that Arsne Wenger can expect to make a handsome profit doubling his money on the 2m Arsenal paid Chelsea for the 22-year-old midfielder only last summer. However, as with Jens Lehmann, who is in talks over a move to his old club Borussia Dortmund, and a third discontented Arsenal player, Gilberto Silva, who is wanted by Juventus, Wenger would prefer Diarra to stay.

The likelihood of that happening is slim and Wenger will not stand in the disgruntled French international's way if terms can be agreed. It means he may reluctantly have to be busier than expected next month and a holding midfielder who is being considered by Wenger is thought to be Panathinaikos's Marcelo Mattos.

Mattos is a 23-year-old Brazilian who is also being considered by Manchester City, Reading and Tottenham Hotspur and would cost around 5m. He has been in impressive form since moving to Greece last summer with Pana keen to keep him. Despite not being an international, he could move to England because he holds an Italian passport.

Discussions are thought to have taken place about Diarra moving to Fratton Park when the two clubs played out a goalless draw on Boxing Day, which meant that Arsenal have now dropped seven points in their last three away games. The Portsmouth manager, Harry Redknapp, is desperate to bolster his squad ahead of the African Nations Cup when he will lose both Papa Bouba Diop and Sulley Muntari and had inquired about Diarra before he left Chelsea.

Diarra has quickly grown frustrated at the Emirates, claiming Wenger had promised he would play around 20 games this season. He has started four although his lack of patience appears curious, especially considering the fine form of Mathieu Flamini, who has had to wait for his chance. Spurs, Aston Villa and Newcastle United are also interested in signing Diarra, as are the French champions, Lyons.

Lehmann's days at Arsenal are also coming to an end. The 38-year-old German had been expected to stay until the summer, having been assured that his place in the Euro 2008 squad was safe as long as he played cup matches, and having only received an offer from Wolfsburg. Borussia Dortmund have now registered an interest with their managing director, Hans Joachim Watzke, and the sporting director, Michael Zorc, flying to London for talks. Lehmann left the club for Arsenal in 2003, and Zorc said: "It is logical that the name Lehmann is linked to us."

Yesterday Wenger said that he would "sit down" with Lehmann, who has lost his place to Manuel Almunia, adding: "I believe first he has to make his own mind up if he wants to stay with us, or not. I, personally, would prefer him to stay.

"I will be sorry to see him go but I don't want to take him out of the team and stop him from playing in the European Championship."

If Lehmann does leave, 22-year-old Lukasz Fabianski would understudy Almunia. The only other goalkeeper at the club close to a first-team appearance is 19-year-old Vito Mannone, who made the bench in the League Cup. It means that Wenger is likely to move for another signing, possibly a stop-gap such as Villa's Thomas Sorensen or Barnsley's Heinz Muller.