Rafael Nadal was pleased to learn that he will be world number one once again; the first time in three years. Nadal said: "For me to be in that position is something very special.
"I have the passion and love for the game. That's why I'm able to be back in that position again."
He was however sorry to know that his ranking was because Roger Federer withdrew from the Cincinnati Masters with a back injury.
Federer, the only player who could have denied Nadal the top spot in next Monday's rankings, was injured in Sunday's Rogers Cup final defeat by Alexander Zverev.
31-year-old Nadal will overtake Britain's top-ranked Andy Murray, who pulled out from Cincinnati as he continues to recover from a hip injury.
Federer expressed his need rest as the US Open draws near, saying: “I am very sorry to pull out of the Western and Southern Open as I always enjoy playing… Cincinnati has some of the best fans in the world and I am sorry I will miss them.
"Unfortunately, I tweaked my back in Montreal and I need to rest this week."