Juan Martin del Potro's return will have to wait.

The 2009 US Open champion has withdrawn from next month's Delray Beach Open as he continues to rehab his surgically-repaired right knee.

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Del Potro has not played since Queen's Club last June. He underwent right knee surgery on June 22nd in Barcelona.

“Our positive thoughts are with Juan Martin as he continues his recovery,” said tournament director Mark Baron. “We look forward to many years of seeing him play healthy tennis in Delray Beach.”

Nick Kyrgios, Milos Raonic, Taylor Fritz, Kei Nishikori, Reilly Opelka and Frances Tiafoe are among the players on the Delray Beach entry list. Tournament organizers still hold three wild cards and two special exempt spots to round out the 32-man singles field.

The 10-day Delray Beach Open will open Valentine’s Day weekend with the ATP Champions Tour team event and a special exhibition match starring Delray Beach's Coco Gauff.

The Team Europe vs Team World match-up will showcase David Ferrer, James Blake, Tommy Haas, Marcos Baghdatis and other fan-favorites.

Photo credit: Western & Southern Open Facebook