Roger Federer, a seven-time champion at the Western & Southern Open, has withdrawn from the 2017 tournament.
"I am very sorry to pull out of the Western & Southern Open as I always enjoy playing here," Federer said. "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."
A lucky loser will replace Federer in the draw and have the benefit of a first round bye. They will play the winner of the opening round match between Diego Schwartzman and Karen Khachanov.
Federer’s withdrawal assures Rafael Nadal will return to No. 1 in the Emirates ATP Rankings when the new rankings are released on Monday, Aug. 21. Nadal, who has spent 141 total weeks in the top spot, will be back at No. 1 for the first time since July 6, 2014.
Nadal’s first time at No. 1 also came as a result of the Western & Southern Open. In 2008, Nadal reached the semifinals in Cincinnati, which allowed him to become No. 1 for the first time on Aug. 18, 2008