Khachanov's Second Wind Meets Blockx's First History

A US Open quarterfinal has a way of stripping a fortnight down to its essentials, and this one arrives with two very different men carrying two very different kinds of relief. Karen Khachanov came to New York off three limp hard-court exits and has quietly assembled the best week of his season. Alexander Blockx, seeded 28th, is already the first Belgian man to reach this stage at Flushing Meadows and the youngest from his country to make a major quarterfinal in the Open Era. Neither has ever faced the other on the senior tour, so there is no rivalry template, no old scar tissue, nothing to lean on except what each man can read in the first twenty minutes.

Khachanov Turned a Bad Summer Into a Good Fortnight

The North American swing read like a man losing faith in instalments. He was flat and serve-disrupted against Bernard Tomic in Los Cabos; in Montreal an early advantage evaporated and his frustration was plain to see in the deciding tie-break; in Cincinnati he took the opening set and was then comprehensively outplayed in the final tie-break. Poor, then competitive but agitated, then close without converting — the profile of a player hunting for conviction rather than riding momentum.

New York changed the weather immediately. His first and third rounds were unusually controlled for a season built on fluctuation: weight, depth, no unnecessary complications. Tournament reporting called his pre-event form "less-than-stellar," and Khachanov's own framing was disarmingly modest — "I'm kind of more an underdog" — with the stated plan of collecting rhythm and confidence one match at a time.

The second-round win over Felix Auger-Aliassime needs an asterisk. Khachanov had lost a tight first set, then began the next two with instant pressure and held his physical intensity, but the Canadian became dizzy and started seeing spots after roughly a set and a half, and his movement, serving and error control fell away. Staying disciplined and refusing to reopen the door counts for something; it was not a clean test against a healthy opponent.

The Learner Tien match was. Khachanov had to solve a younger man who stretched rallies, defended from deep and returned one extra ball every time — "there was always one more ball coming," as he put it. He led in the third-set tie-break, missed a routine backhand into an open court, lost the set, and then won the first four games of the fourth. In the fifth he was broken early, broke straight back, and saved two break points at 3-3. After a run of painful US Open five-setters, he called it special: "This one feels really special." He also allowed that doubt had shadowed his season, and added the line every player clings to — "Everything can change in one week."

No injuries are reported, and his ball speed and movement survived nearly four hours intact. The variable is workload, not health. He has a full day off, and a long history of insisting that opponents know he will "physically stay there" in best-of-five, but a quarterfinal built on repeated neutral rallies would ask the Tien match a second time.

Blockx Has Been Playing With His Hand on His Ribs

Blockx's season has climbed steadily — a summer final, a genuine breakthrough year — but the most instructive recent hard-court match was a defeat. In Cincinnati he served for the win against Flavio Cobolli at 5-3 in the decider and lost four games in a row. His verdict afterwards was honest to the point of bluntness: "I think I just froze a bit."

Then the draw handed him the same opponent in the US Open third round, which is the sort of joke only tennis tells. Cobolli took time away early, attacked, and snatched the first set after Blockx missed an ambitious serve-and-volley in the tie-break. This time Blockx did not shrink. He broke at 4-3 in the second, ran off a long string of games, and combined first-strike power with court coverage nobody expected from him. Cobolli came back from a break down in the fourth and threatened again, but Blockx kept moving him laterally instead of hiding, took the opening a late Cobolli double fault offered, and closed with four well-placed first serves. "I handled those moments better," he said, and he was right.

Against Francisco Cerundolo the tennis was scrappier and more revealing. It became a tight baseline and serving war with almost no separation until Blockx saved three straight break points from 0-40 at 5-5 in the third and Cerundolo double-faulted the set away. That hold was the hinge. In the fourth, Blockx was marginally the calmer man while the Argentine supplied the errors in the last return game.

What he did it on is the concern. Blockx felt a sharp rib or side pain from the second game, had taken medication beforehand, needed more of it plus treatment during the match, and said the discomfort affected his serve. Retirement was live in his mind if he lost the third set: "I was just holding on." The medication began to work late in that set and he served more freely in the fourth, and further treatment afterwards left him feeling better — but no diagnosis and no all-clear have been reported, so his readiness is genuinely unverified. He also played with heavy taping on his left thigh, with no confirmed explanation and no visible restriction once the match settled.

What did not desert him was his movement. L'Equipe singled out his balance, his emergency retrievals and his improvisation on the run, squash forehand included. Over three hours he extended points from compromised positions and made Cerundolo finish rallies again and again. He is also refusing to sound satisfied: "I think I'm still far from my best level."

Who Gets to Stand Still — the Real Question of the Night

Stylistically this is a first-strike contest without a monopoly. Khachanov delivers heavy, linear pace off both wings and enjoys redirecting fast incoming balls; Blockx is aggressive too, but with sharper sudden acceleration, more improvisation and unusually quick defensive coverage for a tall man. US Open analysis described him as powerful, precise and habitually positioned on offence, yet able to blanket the court when forced back. Pure power will not disorganise either of them — waist-high heat is home cooking for both. Direction, height and contact point are the currency.

The first checkpoint is Blockx's service motion. Rib pain interferes with trunk rotation, upward extension and deceleration, and if his serve is compromised Khachanov inherits neutral second balls and can settle in close to the baseline. Worth watching: whether Blockx completes the motion, whether he starts avoiding wide placements, whether pace or belief dips after a long return game. His fourth set against Cerundolo says impairment is not a given.

Khachanov's own trap is the static power exchange. Blockx is at his most dangerous with a predictable cross-court rhythm to accelerate out of down the line, so the Russian's variation needs to be early changes of direction and body serves that make Blockx restart laterally rather than swing from a stable base. Given how well the Belgian defended against Cerundolo, one big forehand may not end the point; Khachanov will likely need two or three forceful changes to finish.

Blockx's route is the mirror image: take the ball early, deny Khachanov preparation time, use short cross-court forehands, returns driven through the middle and sudden redirections behind him to expose a slower first adjustment step. Cobolli briefly did exactly that to Blockx before Blockx reversed it. If he retreats and lets Khachanov build, this becomes the physical examination that ground Tien down — although the same long points are the ones most likely to test a healing rib, and overforcing to shorten rallies would be its own warning sign.

Both men have recently lived and died on a handful of points. Blockx has shown both faces of that coin inside a month: frozen serving for the match in Cincinnati, composed at 0-40 in New York. Khachanov has just broken his own habit of losing US Open five-setters, and his cleanest psychological work was not beating Tien but resetting instantly after gifting away a third-set tie-break. There is no home player and no defending champion here; Khachanov has already quieted a pro-Tien crowd, while Blockx called simply warming up and winning on Ashe "unreal" — a stadium that will lend him neutral goodwill and magnify every pause between points. He has passed his stated goal of the second week and is now playing for a first major semifinal under new coach Ruben Bemelmans, four months after ending sixteen years with Philippe Cassiers. Khachanov is chasing the final weekend of a major again, and a chance to prove that experience and durability still count against the young and the fast.