Jan 3, 2026 — Perth. Sebastian Baez pulled off a gutsy comeback at the United Cup, rallying from a set and a break down to beat World No. 6 Taylor Fritz 4-6, 7-5, 6-4 at RAC Arena. The win gave Argentina a 1-0 lead over the United States in Group E and delivered just the second Top-10 victory of Baez’s career in 20 tries. It was also his first win against Fritz after five losses, a head-to-head that had felt one-sided until today.

“I’m so happy right now!” Baez said after sealing the biggest win of his season so far. The joy was earned. He stared down a scoreboard he had not solved before, then flipped the script with belief and cleaner decision-making when it mattered most.

United Cup shock in Perth: Baez flips a tough matchup

On paper, this looked like Fritz’s match. The American came in ranked No. 6, on a five-match winning streak in their rivalry, and owning one of the heaviest first serves on tour. He played like the favorite early, taking the first set 6-4 and breaking early in the second.

But Baez, the 25-year-old from Buenos Aires and World No. 45, refused to fade. He steadied his serve, defended with heart, and began to drag Fritz into longer, nervy exchanges. Slowly, that early break edge for Fritz vanished. Baez broke late to steal the second set 7-5, then kept pressing on return in the decider to close it 6-4.

“Baez turning 0-5 vs Fritz into a win in Perth feels like a new chapter.”

Mindset shift: from nerves to clarity

Baez admitted the moment felt heavy early. “I felt had my chances in the first set,” he said, explaining that a key service game slipped because “I played so bad because I was too nervous.” He added that he changed his mindset because he had “lost many, many matches against him with the same feeling.”

That honesty showed up in his tennis. In the last two sets, Baez played with more margin on big points, took a step forward on second-serve returns, and showed the composure that had been missing in their past meetings. The result was four breaks of the Fritz serve, a rare achievement against a top server indoors.

Serve numbers: 23 aces do not guarantee a win

Fritz’s serve was fierce in raw speed and aces. He racked up 23 aces to Baez’s 4 and won 77% of points behind his first serve. But the American only landed 55% of first serves (56/102), and Baez made those second-serve looks count.

• Fritz aces: 23; Baez aces: 4
• Fritz first serves in: 56/102 (55%); first-serve points won: 43/56 (77%)
• Baez first serves in: 80/107 (75%); first-serve points won: 51/80 (64%)
• Baez broke Fritz four times

The contrast is simple: Fritz won the flashy points, but Baez owned the pressure ones. The Argentine’s 75% first-serve percentage kept him out of trouble, and his return games were sharp enough to nick breaks despite the ace count across the net.

“How do you lose with 23 aces? Pressure points decide matches.”

Head-to-head reset and career context

Coming in, Baez trailed Fritz 0-5 head-to-head and was 1-18 lifetime against Top-10 opponents. This win moves him to 1-5 against Fritz and 2-18 overall versus the elite bracket. His only previous Top-10 victory came against Andrey Rublev (then No. 8) in the 2022 Båstad semifinals.

That backdrop makes this result more than a single upset. It hints at growth. Baez’s compact frame — 5’7″ and 154 lbs — has always demanded precision, legs, and mindset. Against Fritz — 6’5″, 190 lbs — the physical gap is clear. Yet on this day, the smaller man dictated the moments that decide sets. He did it by landing more first serves, making more returns, and refusing to blink when the rallies tightened.

For context: Baez, born December 28, 2000, turned pro in 2018 and has built his game on fight and footwork. Fritz, born October 28, 1997, turned pro in 2015 and has crafted a top-10 career on pace, power, and a first strike. In Perth, Baez’s patterns outlasted Fritz’s weapons.

“Argentina needed belief; Baez brought it.”

United Cup stakes: Group E tension and a mixed doubles decider

The win gave Argentina a 1-0 cushion in the tie. But Team USA hit back quickly. Coco Gauff posted a commanding 6-1, 6-1 win over Solana Sierra to level the score and force a mixed doubles decider.

That set the stage for a high-drama finish in Perth — exactly what the United Cup was built for. The event runs January 2–11 across Perth and Sydney, features 18 national teams, and puts real weight on the line with $10 million in prize money and ranking points. It is early-season tennis with meaningful stakes.

It was also Baez’s second win in as many days, after he opened his 2026 campaign with a victory over Jaume Munar. The back-to-back level of focus speaks to form and fitness — a handy combo when your country needs you in a team event.

What decided Baez vs Fritz?

Three simple pillars made the difference:

• Mindset reset: Baez admitted nerves, then changed his approach. He trusted his patterns late in the second set and never let go.
• First-serve volume: Landing 75% first serves protected his service games and kept scoreboard pressure on Fritz.
• Return focus: Even against a 23-ace day, Baez made enough returns to earn four breaks — the stat that swung the match.

Fritz can take positives — the serve is clearly firing, and he won a strong share of first-serve points. But he will look at second-serve patterns and point construction in longer rallies, especially at 30-all and deuce. Against a fighter like Baez, those are the small margins that tell the whole story.

The bigger picture

For Baez, this victory checks two boxes: it changes a difficult personal matchup, and it adds a rare Top-10 scalp to his resume. For Argentina, it shows they have a reliable spark at the top of the lineup. In a mixed-team event where every rubber counts, belief spreads fast.

For Fritz and the U.S., the response was immediate with Gauff’s rout to set up mixed doubles. That is the United Cup rhythm: momentum can flip in an hour, and the final word often comes on the doubles court.

In Perth, the final word of the singles session belonged to Sebastian Baez. Down a set and a break to a top-10 star he had never beaten, he found a way. That is how seasons — and sometimes careers — take a step forward.