(Updates with Djokovic quotes and background)
By Julien Pretot
MONTE CARLO, April 26 World number one Roger Federer reached the Monte Carlo Masters final when Serbian Novak Djokovic pulled out of their semi-final on Saturday.
The Swiss top seed was leading 6-3 3-2 when Djokovic complained that he felt dizzy and retired.
Federer will face Rafael Nadal in Sunday's final after the Spaniard beat Russian fourth seed Nikolay Davydenko 6-3 6-2.
"I didn't feel good for the last three days. I've been waking up with a sore throat," said Djokovic.
"But I thought it's not going to be nothing special. But obviously when you're playing against the number one player of the world, you obviously get a lot of balls back and longer points, and I just couldn't get enough energy back after each point.
"I needed a lot of time. And I just decided not to risk anything. I feel dizziness a little bit in the last three days," he added.
"I don't know. The doctor in the tournament couldn't give me the right diagnosis."
In February, Djokovic retired from a Davis Cup match against Davydenko, complaining of feeling dizzy and struggling for breath, following a bout of influenza.
(Editing by Clare Fallon)
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