Roger Federer made a smart decision by pulling out of this month's French Open, world number two Novak Djokovic said on Thursday.

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Roger Federer to skip French Open


VIDEO Roger Federer to skip French Open. 7Sport Roger Federer to skip French Open

Federer, who announced his withdrawal from the year's second major on Monday, said he felt he needed to avoid playing on clay this season to help prolong his career.

The Swiss star has less chance of adding to his 18 grand slam titles on clay than on tennis' quicker surfaces.

"You know, he's very smart in his decision-making... he knows what he's doing," 12-times major winner Djokovic told reporters.

Federer and Djokovic. Image: Getty

"Of course he's aware he has much better chance to win big trophies on quicker surfaces."

Federer defied age and logic to win the Australian Open in January after a knee injury kept him out of tennis for six months, and followed that up with two more high-profile titles at Indian Wells and Miami.

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The 35-year-old world No. 5 is now focused on being in top form for Wimbledon, which begins on July 3 and where he is a seven-times champion.

"Grass obviously is where he feels the most comfortable," Djokovic said.

"I'm not too surprised with this (French Open) decision.

"I mean, he had a lot of matches played at the beginning of the year, and he did amazingly well."

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