KEY BISCAYNE, Fla. (AP) -- Rafael Nadal has resigned as vice president of the ATP Player Council, saying he can no longer give the job the attention it needs.

Nadal denied he was frustrated about unresolved issues in the sport. He pushed unsuccessfully for a two-year ranking system, a proposal opposed by other players, including council president Roger Federer.

Nadal, Federer and others were in agreement on other issues, arguing that the major tournaments are too powerful and players need a stronger voice in decisions. Nadal and Federer were both critical last year of the U.S. Open schedule.

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