Japan's Kei Nishikori will make his ATP Tour comeback at next month's Citi Open, organizers said Friday. The 32-year-old former world No. 4 has been sidelined since last October and he underwent arthroscopic left hip surgery in January. He is currently ranked 116th in the world. The Citi Open will be held July 30-August 7 at the Rock Creek Park Tennis Center in Washington, D.C. Nishikori won the 500-level ATP event, two tiers below a major, in 2015. He has won 12 ATP singles titles to date, with his last win coming at the Brisbane International in 2019.