Chagaev outfoxed his giant opponent to take the title last year

WBA champion Ruslan Chagaev has postponed his heavyweight title fight against Nikolay Valuev due to illness.

The Uzbekistan fighter has a viral infection and his promoters have said he is unable to spar.

Chagaev won a majority decision over the seven-foot tall Russian in April, 2007 and the pair were due to fight again on 31 May.

Valuev won a decision against former WBO champion Sergei Liakhovich in February to set up the fight.

No new date has been scheduled for the bout that was due to take place in Oberhausen, Germany.