Running in Kenya's Great Rift Valley, Emmanuel Mutai's marathon training was intensifying when he began to feel increasingly fatigued. Just three weeks ago, he was diagnosed with typhoid.

But with a London Marathon title to defend on Sunday and the Olympics less than four months away, Mutai wasn't going to let the fever halt his training program in Kaptagat.

"It was in the early stages when I discovered it, so they gave me medication and that helped me," he said Tuesday. "If I was in a critical condition I would not have been able to train ... but I had to reduce my training, the way I used to train, to regain energy."

Although Mutai is feeling better, the lingering effects could harm his performance in Sunday's 26.2-mile race, a year after he broke the course record.

"It is a tough competition this coming Sunday because everyone has run good times, and I have to work extra to try to defend my title," he said.

Mutai is targeting a top-three finish that he says should secure him one of three Kenyan places to compete in the Olympic marathon in August.

"This is the final race and they will use this one to select the team," he said.

Mutai will be competing against five fellow Kenyans, including world-record holder Patrick Makau and world champion Abel Kirui.

"For me, the Olympics, the pressure is there. But what I am more concentrated on is to run well in London," Mutai said. "For me, I see the selection is a bit challenging, but if I manage to be in the top three I have a higher chance of qualifying for the Olympics."

Two of his training partners have collected medals in marathons in recent days, with Henry Sugut winning in Vienna on Sunday and Bernard Kipyego third in Boston on Monday.

"For me this is a good sign," Mutai said. "We have trained a lot together and this shows that my training has been going OK. It definitely gives me confidence for London."


Rob Harris can be reached at http://twitter.com/RobHarris