Frances Tiafoe‘s mid-match walk-off in Montreal is now explained, and it turns out to be more than just fatigue. The American has confirmed he underwent surgery on his right hand immediately after retiring from his third-round match at the National Bank Open, revealing doctors found a cyst that had been bothering him for weeks.

“Sorry to the fans out here in Montreal who came out to watch me tonight,” Tiafoe wrote on social media right after the retirement. “I’ve been dealing with a right hand injury for a lil bit now. I tried to play but need the rest. Until next time, thanks for the love.”

A few days later, he followed up with more clarity on what had actually happened. “Big S/O to Dr. Michelle Carlson and the HSpecialSurgery team,” he wrote. “They were able to diagnose and take out a cyst that has been causing some issues for some time now. Everything went well and I appreciate all the messages and support. I’ll be back soon.”

Seeded No. 15 in Montreal, Tiafoe opened his campaign with a gritty win over Marin Cilic, coming back from a set down to win 5-7, 6-2, 6-2. The same physical issue that ultimately ended his tournament was apparently already bothering him in that match. Against Arthur Rinderknech next, he never found any rhythm and retired while trailing 6-2, 2-0. He flew straight to New York afterward to see Dr. Carlson, an orthopedic surgeon at the Hospital for Special Surgery who specializes in hand, wrist, and upper-extremity injuries.

As alarming as it sounds, this type of injury is actually common in tennis. Ganglion cysts, fluid buildups around a joint or tendon caused by the repetitive stress of gripping and swinging a racquet, are among the most frequent soft-tissue problems in racquet sports. They aren’t cancerous, but they can press on nearby nerves and cause real stiffness or pain as they grow. Most people return to light activity within a week or two after this kind of surgery, though getting back to top-level competition typically takes four to six weeks. Treated properly, it’s a manageable injury rather than a serious long-term one, which is why Tiafoe and his team opted for surgery once the cause was identified, rather than trying to play through it further.

That timeline puts him in a real race against the calendar.

A race against time to be ready for the home slam

The window here is tight. The Cincinnati Open begins August 13, just days after the procedure, with the US Open following three weeks later. Earlier this year, Tiafoe was already forced to skip the Monte-Carlo Masters and Madrid Open due to a separate injury issue, so this marks his second significant fitness setback of the season.

What makes the recovery window sting more is how strong his season had otherwise been. He reached the fourth round at Roland Garros, beat Taylor Fritz in an all-American final at Halle, and was runner-up at the Acapulco Open earlier in the year, climbing back to world No. 20 in the process. Cincinnati carries its own weight for him too, since he reached the final there back in 2023 and has real confidence in his game at that event. Losing practice time right before the US Open, where American fans expect him to make a deep run, is a frustrating way to close out what’s otherwise been one of the more complete seasons of his career.

With a four-week recovery window and the US Open’s main draw set to begin Sunday, August 30, there’s a real chance he ends up skipping Cincinnati entirely just to make sure he’s ready for the tournament that matters most.