Campbell has been given time to recover

The 31-year-old centre-back was substituted at half-time of Arsenal's defeat by West Ham on Wednesday and left Highbury shortly after.

Wenger said afterwards that Campbell was in a bad "mental shape" and he did not train on Thursday.

Campbell's absence deepens Arsenal's problems at the back, with eight defenders now unavailable.

Ashley Cole, Gael Clichy, Lauren, Kerrea Gilbert and Pascal Cygan are out injured and Kolo Toure and Emmanuel Eboue are away at the African Cup of Nations.

Campbell is meant to be leading by example From E Have your say on 606

Campbell's crisis could hardly have come at a worse time for Arsenal, who have just been knocked out of the Carling Cup and the FA Cup and are sixth in the Premiership.

BBC Sport pundit Mark Lawrenson believes the England defender is unfit and in need of a boost.

"Sol Campbell is all over the place. He doesn't look fit and because of his build he looks heavy and ponderous," Lawrenson told BBC Sport.

"He's one of those players that needs to be fit.

"But it can change quickly - he's not suddenly become a bad player, he's just got a few problems."

Campbell strikes me as someone who you need to put your arm around every week Mark Lawrenson

However, Lawrenson feels Campbell will recover from his nightmare performance against the Hammers - and that his early exit on Wednesday will be forgiven.

He added: "The game has changed - in the past a manager would have gone berserk and fined Campbell a week's wages for what he did.