Nishikori ended his 2021 season with a back injury, then had hip surgery in January of this year. He previously went under the knife to address his right elbow on two occasions—in August 2009 and October 2019.
The 2014 US Open finalist turns 33 this coming Thursday. Nishikori, a former world No. 4, is a 12-time ATP champion and holder of 431 tour-level wins. He’s targeting a long-awaited return at February’s Delray Beach Open.