The West Ham United future of Matthew Upson is in doubt.

The Sun says his country mansion in Essex is being marketed by leading estate agents and is understood to be worth in the region of £2million.

Upson insists his chances of making the final 23-man squad for South Africa 2010 will receive a significant boost by playing in the Champions League, like rivals John Terry and Rio Ferdinand.

Liverpool have been long-time admirers of the tough-tackling defender, who is one of only a handful of naturally left-footed centre-backs in the Premier League.

It is also understood that Upson has the same advisor as Liverpool captain Steven Gerrard - his international team-mate.

Upson, 30, has two years remaining on his contract with the Hammers and manager Gianfranco Zola is keen to tie him down on a longer deal.