Alexander Blockx spent three years being described as a prospect. He was the world’s best junior, the first Belgian to win a junior major in more than a decade, and then a player who could not win two matches at a Grand Slam. In 2026 the gap closed quickly: a Challenger title in January, a Masters 1000 semifinal in Madrid in April, a first ATP Tour final in July, and a first Grand Slam quarterfinal in New York in September, reached in his debut appearance in the main draw.
Quick facts
- Full name: Alexander Blockx
- Born: 8 April 2005, Antwerp, Belgium
- Height: 1.93m (6ft 4in)
- Plays: Right-handed, two-handed backhand
- Turned pro: 2022
- Career-high ranking: No. 32 (27 July 2026)
- ATP Tour titles: None
- Junior highlight: 2023 Australian Open boys’ singles champion; ITF junior world No. 1
- Coach: Ruben Bemelmans (from May 2026); previously Philippe Cassiers
Season snapshot — updated 8 September 2026
- Ranked No. 34 at the start of the US Open, seeded 28th — his first seeding at a major
- Career-high No. 32, reached 27 July 2026
- Reached the Madrid Masters semifinals in April, beating Felix Auger-Aliassime and defending champion Casper Ruud
- Reached his first ATP Tour final at Estoril in July, on clay
- Won the Canberra Challenger in January
- Into the US Open quarterfinals on debut, beating Flavio Cobolli and Francisco Cerundolo back to back
Playing style and strengths
The serve is the foundation. At 6ft 4in Blockx generates steep first-serve angles and uses them to shorten points rather than to hunt aces for their own sake, though the aces come: he hit 17 of them past Cobolli in the US Open third round, against five the other way. On the big points at Flushing Meadows he leaned on it heavily, saving 14 of the 17 break points he faced against Cerundolo in the fourth round.
Behind the serve he is a flat, forward-leaning baseliner who takes the ball early off both wings. The ATP’s report on the Cerundolo match credited him with hitting to unusual depth in the closing stages of both the third and fourth sets, pinning his opponent behind the baseline until the errors came. He is comfortable on any hard court and reached his first tour final on clay, which is the surface his junior game was least associated with.
Pressure points and vulnerabilities
The record at majors was thin until this fortnight. Blockx made his Grand Slam main-draw debut at the 2026 Australian Open as a lucky loser and lost in the first round; he then lost in the second round at Roland Garros and the first round at Wimbledon. Before New York he had never won more than one match at a major.
He also has not yet converted a final. Estoril in July was his first at tour level and he lost it, and his title collection remains four Challengers deep. The other open question is physical: he needed treatment for rib pain in the fourth round in New York and said he came close to retiring, which makes the recovery between rounds the variable rather than the tennis.
Career milestones
- 2023: Wins the Australian Open boys’ singles title, beating Learner Tien 6-1, 2-6, 7-6(11-9) in the final — the first Belgian junior Grand Slam singles champion since Kimmer Coppejans at Roland Garros in 2012. Reaches the boys’ doubles final in Melbourne with Joao Fonseca. Rises to ITF junior world No. 1 in May.
- 2023: Makes his ATP Tour debut at Antwerp as a qualifier.
- 2024: Wins his first Challenger title, in Kobe.
- 2025: Records his first ATP Tour main-draw win, over Marcos Giron at the Cincinnati Masters, having come through qualifying. Qualifies for the Next Gen ATP Finals and reaches the final, losing to Tien.
- 2026: Wins the Canberra Challenger in January, breaks into the top 100 in March, and reaches the Madrid Masters semifinals in April — the third Belgian man to reach a Masters 1000 semifinal, after David Goffin and Christophe Rochus.
- 2026: Reaches his first ATP Tour final at Estoril in July and a career-high No. 32.
- 2026: Reaches the US Open quarterfinals on debut, the first Belgian man to do so.
Grand Slam record
- Australian Open: First round (2026), entering as a lucky loser
- Roland Garros: Second round (2026)
- Wimbledon: First round (2026)
- US Open: Quarterfinals (2026)
Background
Blockx was born in Antwerp to a family of Ukrainian descent, and to two athletes: the ATP lists his father Oleg as a hurdler and his mother Natalia as a professional swimmer. He was coached by Philippe Cassiers from childhood through to April 2026 and has worked with the former Belgian tour player Ruben Bemelmans since May. He has represented Belgium in the Davis Cup since 2024.
What to watch next
The immediate question is the rib, and after that the return game. Blockx has built his 2026 on holding serve and taking the one or two chances a set that come back the other way; against opponents who hold as reliably as he does, that is a narrow margin. The tie to watch beyond New York is Belgium’s Davis Cup campaign, where he is now the country’s No. 1 in singles.
Frequently asked questions
How old is Alexander Blockx?
He was born on 8 April 2005 in Antwerp, which makes him 21.
Has Alexander Blockx won an ATP title?
Not at tour level. He reached his first ATP Tour final at Estoril in July 2026 and lost it. He has won four Challenger titles, at Kobe in 2024, Oeiras and Bratislava in 2025, and Canberra in 2026.
What is Alexander Blockx’s best Grand Slam result?
The quarterfinals of the 2026 US Open, reached on his debut in the main draw, which made him the first Belgian man to get that far at the tournament.
Did Alexander Blockx win a junior Grand Slam?
Yes. He won the 2023 Australian Open boys’ singles title, beating Learner Tien in the final, and reached ITF junior world No. 1 that May.
Related reading
- Blockx Went 0-40 Down at 5-5, and Belgium Got Its First US Open Quarterfinal
- Blockx Eliminates Defending Champion Ruud at Madrid Masters
- Francisco Cerundolo Profile
- Flavio Cobolli Profile
- Learner Tien Profile
- Joao Fonseca Profile
- Casper Ruud Profile
- Felix Auger-Aliassime Profile
- ATP and WTA Player Profile Index
