Wenger expects Gallas and Silvestre to sign elsewhere; is Nordtveit part of the solution?

Arsène Wenger expects both William Gallas and Mikael Silvestre to be playing for different teams come the start of the season, according to a brief interview on Arsenal's official website today.  Sol Campbell is "still in no-man's land", according to the manager. 

While this news is not exactly unexpected, to hear it from the man himself adds renewed urgency to the situation at center half.  As of right now, Arsenal's only confirmed senior central defenders are Thomas Vermaelen, Johan Djourou, and Laurent Koscielny.  If one adds Campbell to that list, it looks almost equipped to handle all competitions barring--and this is the rub--injury.

Other potential candidates linger on the fringes to handle duties in the Carling Cup, and depending on opponent, the FA Cup.  Of all of these, one of the most Håvard Nordtveit looked okay against Barnet on Saturday and sounds willing to face the challenge ahead.  He's only 20 years old, which is very young for a center half, obviously, but he does have experience playing in a top European League, having made 19 appearances for FC Nürnberg in the Bundesliga last season.  Interestingly, he featured mainly at defensive midfield for the Bavarian club, which suggests that he could fill in for Alex Song in an emergency situation if need be.  His 6' 1.5" frame appears to have filled out over the past couple of years which will only help in the often-scrappy physical battles that Arsenal center halves have to undertake.

Wenger's comments hint that he may have his eye on one more defensive player with solid experience (something that even Koscielny may lack a bit of at the moment), but it is never easy to tell what will happen with Wenger in the transfer market.  A rotation of Vermaelen, Koscielny, and Djourou is a good core, but maybe it is time for Nordtveit to ease his way in to full-on English football in some capacity.