Top-ranked Novak Djokovic says he will skip the hometown tennis tournament organized by his family because of the death of his grandfather.

Djokovic said Wednesday he felt emotionally drained and unable to summon the mental strength since his grandfather died last Thursday.

Djokovic says his decision to miss the Serbia Open, which starts Monday in Belgrade, "was one of the most difficult decisions in my career, but it is impossible for me to play and think about tennis."

Djokovic lost to second-ranked Rafael Nadal in the Monte Carlo Masters final on Sunday, three days after his grandfather's death.