Adolfo Daniel Vallejo Álvarez (born 28 April 2004) is a Paraguayan professional tennis player. He has a career-high ATP singles ranking of world No. 52 achieved on 5 October 2026 and a doubles ranking of No. 435 achieved on 21 April 2025. He is currently the No. 1 singles player from Paraguay.
He reached an ITF junior combined ranking of world No. 1 on 15 August 2022.
Vallejo represents Paraguay at the Davis Cup, where he has a win–loss record of 5–3.
Career 2021-2022: Juniors In 2021, Vallejo won the prestigious Orange Bowl in Plantation, United States, defeating American Bruno Kuzuhara in the final. He was the first Paraguayan player to win that event and only the second to reach the final after Víctor Pecci.
In January 2022, he was a runner-up in the boys' doubles category at the 2022 Australian Open, with American Alex Michelsen. The pair lost to second seeds Bruno Kuzuhara and Coleman Wong in the final.
2023-2024: Maiden ATP Challenger title In July 2023, Vallejo reached his first final on the Challenger Tour in Santa Fe, Argentina, losing to Mariano Navone in the final. The following month, he won his first Challenger doubles title in Lima, Peru, partnering with Gonzalo Bueno, defeating Jorge Panta and Ignacio Buse in the final.
In March 2024, Vallejo won his first Challenger title in São Léopoldo, Brazil, defeating Enzo Couacaud in the final. He became the youngest Paraguayan to win an ATP Challenger title and the fourth Paraguayan champion in ATP Challenger Tour history and first since Ramon Delgado in 2009. As a result, he reached the top 300 on 6 May 2024.
2025: Two Challenger titles, top 150 In March 2025 ranked at a career-high of No. 187, achieved on 17 March 2025, Vallejo reached the semifinals at the home Challenger in Asunción, Paraguay but lost to eventual champion Emilio Nava. Following winning the 2025 Guayaquil Challenger, Vallejo reached the top 150 in the singles rankings at world No. 143 on 24 November 2025.
2026: Top 100, Grand Slam debut and first win, tour-level semifinal Vallejo began his year by winning two consecutive Challenger titles in Itajaí and Concepción. He reached a third final in the South American clay court swing in Brasília, but lost to Henrique Rocha.
Following a first round win at Houston, Vallejo made his debut in the world's top 100, becoming only the fourth Paraguayan player ever to do so, and the first since Ramón Delgado. In Madrid, Vallejo qualified to make his Masters 1000 debut, then defeated Grigor Dimitrov, becoming the second Paraguayan player after Delgado to win a match at Masters 1000 level, and 17th seed Learner Tien to advance to the third round, where he lost to Flavio Cobolli in straight sets. After this, he advanced to his fourth challenger tour final of the year in Valencia, losing to Miomir Kecmanović in 3 sets. At the French Open, Vallejo advanced to the second round after 20th seed Cameron Norrie was forced to retire midway through their match. He lost in the second round to Moïse Kouamé.
During an interview following the loss to Kouamé, Vallejo made controversial sexist remarks about chair umpire Ana Carvalho, arguing that female umpires and officials are unfit to umpire matches like his and Kouamé's due to the demanding crowd. He was quoted saying "This sort of match needs to be umpired by a man; it’s very difficult for a woman to do it". The French Open organizers released an official statement condemning Vallejo's actions, and he was subsequently fined €65,000 (equivalent to roughly US$75,000) for his remarks, the largest fine in Roland Garros history. [en: Sexist comment directed at referee results in largest fine ever at Roland Garros]
Vallejo made his first ATP Tour-level semifinal in Båstad. He made his debut inside the top 60 after a first round win in Winston-Salem.
Performance timeline
Singles Tournament20252026SRW–LWin%Grand Slam tournamentsAustralian OpenQ2Q30 / 00–0French OpenA2R0 / 11–1WimbledonA1R0 / 10–1US OpenA1R0 / 10–1Win–loss0–01–30 / 31–3ATP 1000 tournamentsIndian Wells OpenAA0 / 00–0Miami OpenAA0 / 00–0Monte-Carlo MastersAA0 / 00–0Madrid OpenA3R0 / 12–1Italian OpenAQ10 / 00–0Canadian OpenA1R0 / 10–1Cincinnati OpenA3R0 / 12–1Shanghai MastersA0 / 00–0Paris MastersA0 / 00-0Win–loss0–04–30 / 34–3
ATP Challenger Tour finals
Singles: 11 (5 titles, 6 runner-ups) Finals by surfaceHard (–)Clay (5–6)
ResultW–LDateTournamentTierSurfaceOpponentScoreLoss0–1Challenger Santa Fe, ArgentinaChallengerClay Mariano Navone2–6, 4–6Win1–1São Léo Open, BrazilChallengerClay Enzo Couacaud6–3, 6–2Loss1–2Antofagasta Challenger, ChileChallengerClay Juan Manuel Cerúndolo6–3, 2–6, 4–6Loss1–3Challenger de Tigre, ArgentinaChallengerClay Juan Pablo Varillas4–6, 4–6Win2–3Curitiba Challenger, BrazilChallengerClay Pedro Boscardin Dias6–3, 7–5Loss2–4Costa do Sauípe Open, BrazilChallengerClay Román Andrés Burruchaga1–6, 2–6Win3–4Challenger de Guayaquil, EcuadorChallengerClay Juan Pablo Varillas7–5, 6–7(7–9), 6–3Win4–4Itajaí Open, BrazilChallengerClay Thiago Seyboth Wild7–5, 4–6, 6–2Win5–4Challenger Concepción, ChileChallengerClay Alejandro Tabilo6–2, 1–6, 6–1Loss5–5Brasília Tennis Open, BrazilChallengerClay Henrique Rocha4–6, 4–6Loss5–6Copa Faulconbridge, SpainChallengerClay Miomir Kecmanović2–6, 6–3, 2–6
Doubles: 1 (title)
ResultW–LDateTournamentTierSurfacePartnerOpponentsScoreWin1–0Lima Challenger, PeruChallengerClay Gonzalo Bueno Jorge Panta Ignacio Buse6–4, 6–2
ITF World Tennis Tour finals
Singles: 6 (4 titles, 2 runner-ups) Finals by surfaceHard (1–1)Clay (3–1)
ResultW–LDateTournamentTierSurfaceOpponentScoreLoss0–1M15 Madrid, SpainWTTHard David Jordà Sanchis3–6, 1–6Loss0–2M25 Rosario, ArgentinaWTTClay Juan Ignacio Londero3–6, 2–6Win1–2M25 Idanha-a-Nova, PortugalWTTHard Alastair Gray6–2, 6–3Win2–2M25 Punta del Este, UruguayWTTClay Luciano Emanuel Ambrogi6–1, 6–4Win3–2M25 Mar del Plata, ArgentinaWTTClay Lautaro Midón7–6(7–4), 6–3Win4–2M25 Londrina, BrazilWTTClay Gustavo Heide6–4, 4–6, 6–3
Doubles: 7 (5 titles, 2 runner-ups) Finals by surfaceHard (4–1)Clay (1–1)
ResultW–LDateTournamentTierSurfacePartnerOpponentsScoreWin1–0M15 Los Angeles, USWTTHard Ethan Quinn Aidan Mayo Keenan Mayo7–5, 6–4Win2–0M15 Fountain Valley, USWTTHard Ethan Quinn Abraham Asaba Sekou Bangoura6–0, 3–6, [10–8]Loss2–1M25 Trnava, SlovakiaWTTHard (i) Daniel Rincón Mats Hermans Mick Veldheer6–1, 3–6, [8–10]Win3–1M15 Trnava, SlovakiaWTTHard (i) Daniel Rincón Abedallah Shelbayh Coleman Wong6–4, 6–2Win4–1M15 Manacor, SpainWTTHard Daniel Rincón Svyatoslav Gulin Ilya Snițari6–4, 7–6(7–5)Loss4–2M15 Antalya, TurkeyWTTClay Igor Gimenez Matteo De Vincentis Arthur Reymond6–7(5–7), 4–6Win5–2M25 Carnac, FranceWTTClay Federico Agustín Gómez Christoph Negritu Alexander Merino6–3, 7–5
Junior Grand Slam finals
Doubles: 1 (runner-up) ResultYearTournamentSurfacePartnerOpponentsScoreLoss2022Australian OpenHard Alex Michelsen Bruno Kuzuhara Coleman Wong3–6, 6–7(3–7)
References
External links