Macrozonaris took advantage of a slow start from Montgomery

Tim Montgomery's season got off to the worst possible start as he was beaten by Canada's Nicholas Macrozonaris at the Grand Prix Banamex in Mexico.

The American boldly said before the race that he would be targeting his world record, but he finished in 10.04 seconds behind Macrozonaris, who clocked 10.03secs.

"I am very surprised," Montgomery said.

"This is the first race of the year. I think I had a bad start today. That is what happened."

American Jon Drummond was third in 10.07secs, while Britain's Darren Campbell finished sixth.

The Olympic 200m silver medallist later clocked 20.51secs in his favoured event as he finished third behind America's Coby Miller and Emedolu Uchenna of Nigeria.

"Really I came here to see if my preparations for the season have been the right ones," said Campbell, planning to tackle both the 100 and 200m in August's World Championships.

"The first race is always a difficult one and I suppose I am happy that I got a placing."

Jamie Baulch, who has been training with Campbell in the United States, finished down the field in the sixth.

"I'm looking for speed and planning a few more early season 200s before my first 400m," said the world indoor bronze medallist.

Guevara delighted the home crowd by breaking the 300m world record

Elsewhere, Mexico's Ana Gabriela Guevara broke the 300m world record with a time of 35.30secs.

Last year's 400m world number one broke the old mark of 35.46secs set by England's Kathy Cook in August 1984.

Ionela Tirlea of Romania was second in 36.20secs while Olympic 400m champion Cathy Freeman of Australia finished third in 36.42secs.

Freeman, who took a sabbatical after the 2000 Sydney Olympics and further time off to help deal with her former husband's throat cancer, said she was relieved to be running again.

"I know I have to be really patient," she said. "I think my career has a long way to go."