Stefanos Tsitsipas has spent the past two years hearing his career described in the past tense. On Monday night at Louis Armstrong Stadium, the former world No. 3 answered back — dragging himself from a set and a break down to stun 10th-seeded Arthur Fils, the reigning Cincinnati Masters champion, 4-6, 7-6(3), 6-1, 6-4 in the first round of the 2026 US Open.

The scoreline barely captures how lopsided this rivalry had been. Fils, 21, had won all five of the pair's previous meetings, including a brutal 6-0, 6-1 beatdown in Miami this past March that took just 55 minutes. He arrived in Flushing Meadows as one of the tournament's hottest names, having beaten Frances Tiafoe in the Cincinnati final barely a week earlier to lift the biggest title of his young career.

None of that mattered once Tsitsipas — unseeded and ranked all the way down at No. 53 — found his range. Fils served for the second set at 5-3, only to unravel with a double fault that let Tsitsipas back into the tiebreak, which the Greek ran away with 7-3. From there, per ATP Tour's match recap, Fils never located his rhythm again, dropping the final two sets as Tsitsipas closed it out in just over three hours.

"Almost Unprofessional"

Fils did not sugarcoat the collapse afterward. "At my level, to do such a mistake is almost unprofessional," he admitted, according to TennisUpToDate's account of his press conference. "Once the energy went down at the end of the second, I never felt again a good energy." He was gracious about the outcome even so: "He played better than me, so he deserve to win."

"AT MY LEVEL, TO DO SUCH A MISTAKE IS ALMOST UNPROFESSIONAL." — ARTHUR FILS

The loss extends a grim pattern for Fils at majors — he has won just a single match across his last six Grand Slam appearances, with a second-round showing at Wimbledon 2025 standing as his best result, a run hampered by a back injury that has dogged him on and off since Rome. Hard-court form and Grand Slam form, for Fils, remain two very different animals.

For Tsitsipas, the win is the clearest sign yet of a season spent quietly rebuilding. The two-time major finalist, who reached the Australian Open title match in 2023, has slid outside the top 50 amid injuries and inconsistent form, and few gave him a prayer against a player who'd owned him for three straight years. "I'm speechless. I don't know what to say. It's an amazing start to the tournament," Tsitsipas said afterward, before turning reflective about his broader comeback. "Let go of expectations... carrying that heavy boat is not easy during a match."

Asked whether a result like this meant he could climb back toward the sport's summit, he didn't rule it out. "Why not? I'm taking it a day at a time," he said. "A win like this today matters a lot to me."

Multiple outlets covering the tournament, including Yahoo Sports, singled out the result as the most shocking of the entire first round at Flushing Meadows — a bigger jolt, by seeding gap and head-to-head history, than several of the tournament's other early upsets.

Tsitsipas now moves into the second round, where a run deep into the second week would mark his best Slam showing in more than a year. Fils, meanwhile, heads home to regroup before the ATP's fall hard-court swing, still searching for the Grand Slam breakthrough that has eluded him even as his ranking has climbed.