Rafael Nadal's doctor is optimistic about the world No. 1's hip injury

Rafael Nadal's injury will not take as long to heal as some of his other recent problems but still requires rest and rehab, according to his doctor.

Nadal experienced the injury during his five-set quarterfinal against Marin Cilic at the Australian Open, calling the trainer and then playing for a few games before stopping down 0-2 in the fifth set. In a statement, Nadal's team said the problem would keep him off the court for three weeks but that he still planned to play his next scheduled event at Acapulco.

Angel Ruiz Cotorro, in an interview with El Espanol, said the injury was relatively unusual for a tennis player.

"What Rafa has is an injury of a hip flexor muscle," he said to the newspaper. "It has become inflamed, causing an intramuscular Grade I injury. The tendon is not inflamed so the forecast is good. Logically, we will have to be cautious for two or three weeks, with rest and physiotherapy. Then little by little, we can incorporate physical activity."

There is no "rupture" of the muscle, added Cotorro, who pointed to Nadal's tough back-to-back encounters in the fourth round and quarterfinals.

"The meeting with Schwartzman was very tough and they played at a very high temperature," he said. "Then another intense match with Cilic, with a lot of changes of rhythm.

"All muscular injuries are aggravated when forced. Rafa was very limited [in the quarterfinal], and the decision to retire was a correct one," he said.

Nadal, who finished his season with knee problems and had to delay his offseason training, noted that his buildup to the Australian Open was not as good as the year before, which could have also played a role.

"Maybe if I had the chance to work as hard as I worked, maybe will not," he said following the match. "But was not the case. I had the knee, and I had to go slower, step by step."

The 31-year-old withdrew from the Abu Dhabi exhibition and Brisbane, and he did not play any warmups before the tournament.

Nadal will stay No. 1 in the rankings.

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