DOHA • After bowing out 3-6, 6-1, 7-5 to Georgian Nikoloz Basilashvili in the quarter-finals of the Qatar Open, Roger Federer admitted on Thursday he is still not at "100 per cent yet" and would need another "five to six weeks" more to build up his fitness.

As such, the 39-year-old Swiss has pulled out of next week's ATP Dubai Open to spend more time on the practice courts.

Having not played competitively for nearly 14 months - this was his first outing since last year's Australian Open - and against the backdrop of two knee operations, Federer looked rusty in his two three-set matches here.

It was always a tall order for him to win a fourth title in Qatar, but the world No. 6 insisted the tournament was just a "stepping stone" as he targets full fitness for the grass-court season.

"It's been great to be back on the @atptour, loved every minute playing in Doha once again," tweeted the men's record 20-time Grand Slam title winner.

"A big thank you to the best and loyal team that helped me get here. I've decided it's best to go back to training and as a result, I've decided to withdraw from Dubai next week.

"I've come from so far away that I'm actually happy that I was able to play back-to-back three-set matches against top players.

"That's an important step forward for me. I know that I'm still building up, this is a stepping stone."

Looking ahead, Federer, who will also skip the opening Masters event of the season in Miami this month, has yet to decide on other events before Wimbledon or the Tokyo Olympics but hinted that he might give Roland Garros a shot.

"What comes before the grass courts are the clay courts. So from that standpoint, I have no choice but to play on clay if I want to play matches," he said. "It could be good for me, the clay. It could be bad for me, the clay. So I will only know in practice, but I don't think it's going to be bad, to be honest.

"I'll just see how much workload the body and the knee still takes and what's the best way to prepare all the way for basically the beginning of the season for me, which is the grass-court season."​

Playing back-to-back days has, however, taken its toll.

"The whole shoulder has muscle pain, but that comes with the pressure," he said. "When you've got your back against the wall, you've got to crank one out. Overall, the body is actually fine. I'm happy, it could be much worse."

In another upset, Spain's Roberto Bautista Agut beat Austrian top seed and US Open champion Dominic Thiem 7-6 (7-3), 2-6, 6-4 to set up a last-four clash with Andrey Rublev yesterday.

The Russian made the semi-finals without hitting a ball after a first-round bye, and then injury-enforced walkovers by Richard Gasquet and Marton Fucsovics.

AGENCE FRANCE-PRESSE, REUTERS

ATP QATAR OPEN

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