DUBAI – Novak Djokovic's bid to close the gap on Roger Federer and Rafael Nadal at the top of the world rankings carried him to the semi-finals of the Dubai Open after a 6-3, 6-4 win over Marin Cilic on Thursday.
But third seed Andy Murray, who began 2009 as favourite to win the first Grand Slam of the year, was forced to withdraw from the tournament with a virus.
Former Australian Open champion Djokovic had struggled in his previous match against the Czech Jan Hernych, but the Serbian played more solidly during his victory against Croatia's Cilic, who has broken into the top 20 for the first time this year.
"I am very happy that my performance was much better than in the previous two days, but I was lucky to get through some service games," said Djokovic, referring to the fact that he was 15-40 down while closing out the first set and twice break point down before reaching 5-3 in the second.
"He had chances in both sets, so it's good to go through. But that's thanks to the great atmosphere and support.
"Here at Dubai I always feel at home," he continued, before paying tribute to his next opponent, Gilles Simon, who he said is "consistent and solid from both sides".
Frenchman Simon, the third seed, earned the chance to reach the eighth final of his career by ending the long and, at times, remarkable record of his compatriot Fabrice Santoro at this tournament.
Simon's 7-6 (7/3), 6-1 victory over the 36-year-old crowd favourite carried him to the semi-finals.
Meanwhile, Murray, admitted that he has been hindered by illness ever since the Australian Open.
The world number four from Britain has the best record on the men's tour this year with 15 wins from 16 matches, but suddenly the future is looking uncertain after the revelations about his long-term medical condition.
Murray began to feel worse after his impressive straight-sets second round win over Arnaud Clement on Wednesday.
"I woke up in the middle of the night sweating," he said.
"I went to the doctor and started taking antibiotics, but I have felt very tired all week. I have felt cold and shivery and had a sore throat, I feel that my temperature is up, and my body feels bad."
There had also been rumours that Murray, who pulled out of the Marseille tournament last week, might pull out here with an injury to his right ankle, but he confirmed that there had been no serious problem with it in Dubai.
However, there will be doubts about his ability to play in the Davis Cup tie for Britain against the Ukraine in Glasgow next week.
"I will have to rest and see," he said. "If I feel bad I won't play, and if I feel fine I will play," he said.
The worry is that Murray is developing a form of mononucleosis (glandular fever), something which hit Federer last year, and contributed to Justine Henin's retirement in 2008.
"I've had a blood test, and I've had antibiotics before for five or six days, " he said.
Murray's withdrawal meant that another Frenchman, Richard Gasquet, received a walk-over into a semi-final against David Ferrer of Spain.