Torres in race to be fit for World Cup
The 26-year-old underwent an operation on his right knee last month and is now working six hours a day in a bid to face the Swiss on June 16.
"Right now, we cannot say whether Fernando will be ready in time for the first match against Switzerland - there are still many days and the injury evolves day to day," said Spain team doctor Juan Jose Garcia Cota.
"He has started to work outside and is still doing gym work to improve the muscle tone around the knee.
"It takes a long time but the process we are following is still very good. We cannot say for sure but we are optimistic."
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