Federer, 28, won his first French Open title last year after he overcame Soderling in the final, but should Rafael Nadal regain his crown and seal a fifth title this year he will leapfrog the Swiss champion to the top of the ATP rankings.
The Swiss, who yesterday failed to reach a Grand Slam semi-final for the first time in 23 tournaments, was unhappy at the damp weather which he believed favoured his Swedish opponent.
“I’m not blaming the conditions or anything, but I think they were in his favour towards the end,” said Federer.
“If you serve 225-230kph, you can still hit through the court on the serve. I may be lacking those five to 10ks extra to hit through a guy on the serve.
“Of course, I’m disappointed to have lost three matches in the rain on clay this season: in Estoril, in Rome, and now here again.”
When asked about the prospect of losing his No.1 ranking, Federer said he was more disappointed about his run in Paris coming to an end.
“I am most disappointed that I can’t defend my title here,” he added. “I really felt like my tennis was good enough to come here and do it again, but that was not the case.”
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BIOGRAPHY: Danny Rose
BIOGRAPHY: Antoine Griezmann