New Arsenal signing Sol Campbell has taken legal action against former club Portsmouth.

The Telegraph says Portsmouth's troubled owners are facing yet another challenge to their finances after former club captain Campbell issued a writ for £1.7 million in allegedly unpaid image-rights fees and bonuses.

His claim, detailed in a writ lodged with the High Court earlier this month, suggests that the club may have been struggling to pay their players on time long before the troubles of recent months.

It also offers an insight into the value and structure of incentives and image-rights deals for players at the top of the game.

According to Campbell's writ, Portsmouth agreed to pay the centre-half £20,000 a week, rising to £30,000 in the last two years of his contract, in exchange for allowing the club to use his image in commercial, sponsorship and endorsement deals.

Campbell received the payments on top of his wages, which the writ maintains had reached £30,000 a week in the 2008-09 season.