Lars Boom has to postpone his cyclo-cross comeback. The former world champion suffers from gastroenteritis and is unable to participate in the Scheldecross in Antwerp (Saturday) and the World Cup race in Namur (Sunday).

"Because of a persistent stomach flu and fever, I can not start in Antwerp and Namur this weekend. I am very frustrated," Boom tweeted yesterday.

If he has recovered, Boom will make his comeback on Saturday, December 26. On Boxing Day, he plans to do the World Cup race in Heusden-Zolder. Three days later the Azencross in Loenhout is on his schedule.

On Sunday, January 31, Boom plans to be at the start of the World Championships. The 29-year-old Dutchman last did that race in 2009. Back then he was only 20th in Hoogerheide despite lining up as the defending champion. Since then he has been focused on his road career.