 Complete the following phrase:  Karpov defended his FIDE title against the rising star Gata Kamsky 639 in 1996. In 1998, FIDE largely scrapped the old system of Candidates Matches, instead having a large knockout event in which a large number of players contested short matches against each other over just a few weeks. In the first of these events, the FIDE World Chess Championship 1998, champion Karpov was seeded straight into the final, defeating Viswanathan Ad 222, rapid tiebreak 20. In the subsequent cycle, the format was changed, with the champion having to qualify. Karpov refused to defend his title, and ceased to be FIDE World Champion after the 