Jason Kubler

While competing on the ITF Junior circuit, Kubler made his professional debut in September 2008 at the Australia F7 Futures event in Gympie.

After continued success on the junior circuit, Kubler was granted wildcards into the Brisbane International and Sydney International qualifying draws to begin 2010. Despite losing in the first round of qualifying at both Brisbane and Sydney, Kubler was given another wildcard to make his ATP and Grand Slam debut at the 2010 Australian Open. Drawn against the 24th seed, Ivan Ljubičić, Kubler was handily beaten 6–2 6–1 6–1 in a lacklustre display. Following his defeat at the Australian Open, Kubler travelled to Europe to compete in more Futures events but failed to proceed past qualifying at any tournament. Towards the end of April, Kubler successfully gained his first-ever ATP point in an Australian Futures event held in Ipswich, where he went on to reach the final, losing to Brydan Klein in straight sets. Kubler's best results for the remainder of 2010 were semi-final appearances at Netherlands F2, Italy F23, Portugal F5 and Spain F37 Futures events. He finished the season ranked 535 in the world.

After an injury plagued start to 2011, Kubler travelled to Spain in March for three Futures events that resulted in just one main draw win. Further injuries kept Kubler on the sideline until August, where he again had limited success in tournaments across Europe. Back-to-back wins in Birmingham and Niceville in October and November salvaged a frustrating year for Kubler, who finished the season with a world ranking of 530.

No longer playing on the junior circuit, Kubler began 2012 by entering four Futures tournaments in Florida after bypassing the Australian summer. Kubler lost in the final of USA F1 to Jack Sock and USA F3 to Brian Baker before winning the USA F4 event in Palm Coast to cap off an excellent start to the year. Kubler returned to Australia in March, where he lost the final of the Ipswich Futures event against Sam Groth but defeated John Millman to claim the Bundaberg Futures title. Kubler then headed to Europe, to compete in further Futures tournaments and the first Challenger events of his career, where he made a quarter-final at the Todi Challenger in September. Following more success on the Futures tour, Kubler reached a career-high ranking of 268 on 29 October 2012. In 2013, Kubler played in Futures tournaments throughout the US, Spain, Great Britain, Australia, Italy and Egypt, but only on clay due to ongoing knee issues. He won three Futures tournaments for the year but saw his ranking drop to 397 to end the season.

Kubler at the 2015 Wimbledon
qualifying tournament

Kubler again didn't enter the Australian tournaments in January/February, opting to play Egypt and Spain Futures instead. This would prove successful as he entered six tournaments, making the final of three and winning one. He then qualified for the main draw of the challenger events in Panama & Colombia and then competed in Savannah & Tallahassee, making the second round in both. In May, Kubler qualified for the ATP event in Düsseldorf, his first ATP World Tour event since the 2010 Australian Open. He won his first tour-level match by defeating Alessandro Giannessi, before losing to Denis Istomin in the second round.[10] In June, Kubler returned to the Futures circuit and defeated the #1 seed Kimmer Coppejans in the final of The Netherlands F3 in Breda. This was the title of his 9th future. He broke into the top 200 for the first time on 25 August at 197. In September, Kubler made the quarter-final of the Biella Challenger and the following week, he won the Sibiu Challenger.[11] This was his first Challenger title.[12] On 24 November, Kubler reached a career high ranking of 136 before finishing the year with an ATP ranking of 140. Kubler played a total of 29 tournaments in 14 countries in 2014, all of which were on clay, due to his ongoing knee problems.[13]

Kubler skipped the Australian leg again, instead of playing in the Colombia and Santo Domingo challengers and qualifying rounds of Quito Open before playing in the United States Challengers throughout April; his best result being a quarter-final in Sarasota. In May, Kubler made the second round of Heilbronner Challenger before the French Open, where he lost in round 1 of qualifying to Tim Pütz. In June, Kubler entered the qualifying rounds of Wimbledon, thus his first competitive appearance on the grass in three years.[14] He defeated Rui Machado in straight sets in round 1 but lost in round 2 to Aleksandr Nedovyesov who went on to qualify for the main draw. In July, Kubler qualified for the Braunschweig Challenger and made round 2 of Poznań Challenger. In September, Kubler lost in round 1 of US Open qualifying, before undergoing knee surgery. He finished the year with a world ranking of 544. After rehabbing from knee surgery, Kubler commenced 2016 by playing on the ITF circuit in the US, where he reached the quarter-final of USA F6 and semi-final of USA F8 in February. At USA F9 in March, Kubler retired in the first round. In May, just eight months after his last surgery, Kubler underwent the sixth knee operation of his career which sidelined him for the rest of 2016.[15] As a result, Kubler finished the year ranked outside the world's top 1000.

After a year out of the game and without a world ranking, Kubler returned to professional tennis in March at the Canberra ITF Futures tournaments. In an interview with the Canberra Times, Kubler was quoted as saying "I'm really happy to be back playing again but at some point, I've got to ask myself do I really want another knee operation. If I get another injury I'll seriously consider giving it (tennis) away."[4] After little success in Canberra, Kubler travelled to Europe in April for Futures events in Spain and Italy. Although Kubler managed to make a semi-final appearance at Spain F12, the highlight of his European trip was a doubles title with compatriot Alex Bolt at the Italy F14 tournament. This was Kubler's first professional trophy of any kind since 2014.

Following a three-month absence, Kubler returned in September for a series of Futures events in Australia. Despite an early exit in Brisbane, Kubler made back-to-back finals in Toowoomba and Cairns to improve his world ranking to 615. In late October, Kubler won through qualifying at the Traralgon Challenger and made a remarkable run to the final after defeating two former top 100 players in Taro Daniel and Matthew Ebden. He defeated Alex Bolt in the final to claim his first Challenger title since 2014, which skyrocketed his ranking inside the world's top 350. At the Canberra 2 Challenger in November, Kubler was defeated in the second round by Omar Jasika. Kubler was expected to compete in the Australian Wildcard Playoff in December for a spot in the 2018 Australian Open, but ultimately withdrew alongside a host of top-seeded players.[16] Kubler finished the year ranked 341 in the world.

Kubler started his 2018 campaign at the Playford Challenger in South Australia, which he won after qualifying. The victory saw Kubler move inside the world's top 250 for the first time since 2015. Following an impressive run on the Australian Pro Tour and a huge improvement in ranking over the last six months, Kubler was awarded the final wildcard into the 2018 Australian Open, his first Grand Slam appearance in eight years.[17] Kubler faced 10th seed Pablo Carreno Busta in the first round, where he lost in a highly competitive four-set match 5–7 6–4 5–7 1–6. Kubler showed plenty of promise in the match, leading by a break in both the first and third sets, but failed to capitalise on his opportunities. Following the Australian Open, Kubler competed in nine Challenger events across Australia and Asia from February to May. His best results through this stretch included three semi-final appearances at the Burnie International, Quijing International and Seoul Open. Kubler improved his world ranking to 160 following the Asian swing, his best world ranking in three years. At the French Open, Kubler lost in the first round of qualifying to Goncalo Oliveira. Following the French Open, Kubler proceeded to lose in the first round at his next three Challenger tournaments before making a semi-final run at the Ilkey Trophy, where he eventually lost to German Oscar Otte. The result saw Kubler return to the world's top 150 for the first time in more than three years.

Kubler then entered the Wimbledon qualifying tournament and showed good form through his first two matches, defeating Arthur De Greef and Adam Pavlasek. In the final round of qualifying, Kubler defeated Canadian journeyman Peter Polansky in four-sets to qualify for the Wimbledon main-draw for the first time in his career. Heading into Wimbledon, Kubler's remarkable comeback story to the tour started to gain some attention, and his journey was captured by the ATP in a video feature titled "The Comeback Story of Jason Kubler".[18] Kubler faced unseeded Argentinian Guido Pella in the first round, where he lost in four close sets 4–6 5–7 6–4 6–7. Following Wimbledon, Kubler entered the Winnipeg Challenger. As the fourth seed, Kubler dropped just one-set the whole tournament to claim his second Challenger title of the year, defeating Lucas Miedler 6–1 6–1 in the final. The result saw Kubler move to 114 in the ATP rankings, eclipsing the career high he set way back in November 2014. To finish his Canadian tour, Kubler made the semi-final of the Gatineau Challenger before withdrawing from the Granby Challenger with knee soreness. The results moved Kubler to a world ranking of 105.

Kubler then attempted to qualify for the Washington Open, an ATP 500 event. Despite losing in the final round of qualifying, Kubler was granted entry into the main draw as a lucky loser after Nick Kyrgios withdrew with a hip injury. Taking Kyrgios' seeding, Kubler progressed through to the second round via a bye before losing in a third set tie-breaker to fellow Australian James Duckworth. In August, Kubler was granted a reciprocal wildcard into the US Open.[19] In the lead up to the tournament, Kubler competed in the Vancouver Open on the Challenger circuit, where he was defeated by Dan Evans in the final. The result propelled Kubler into the Top 100 for the first time, marking an 841 place ranking rise in the past 12 months.[20] At the US Open, Kubler upset 19th seed Roberto Bautista Agut 6–3 6–3 6–4 in the first round to claim the first main-draw grand slam win of his career.[21] In the second round, Kubler was forced to retire in the fourth-set against American Taylor Fritz after rolling his ankle.[22]

Kubler competed in three tournaments to close the year but failed to progress past the second round at any event. He finished the season ranked 114 in the world, the best end-of-year ranking of his career.

Kubler was expected to compete in the Brisbane International, but withdrew from the event due to knee soreness.[23] Kubler then attempted to qualify for the Sydney International, but fell in the first round to third seed Yoshihito Nishioka. For the second consecutive year, Kubler was awarded a wild card into the 2019 Australian Open.[24] With limited tournament preparation, Kubler was defeated in the first round of the Australian Open by unseeded Italian Thomas Fabbiano in four sets.

Following a three-month break from the tour, Kubler returned in mid-April at the Kunming Challenger where he was defeated by James Duckworth in the third round. At the 2019 French Open, Kubler attempted to qualify but fell in the second round to Viktor Troicki. Kubler then competed in three Challenger tournaments in the lead up to Wimbledon but failed to make it past the second round at any event. At Wimbledon, Kubler won through his first two matches in qualifying but fell at the last hurdle to Yasutaka Uchiyama in five-sets. Following his poor results, Kubler's ranking dipped to 211 in the world. In July, Kubler made back-to-back finals on the Challenger tour in Winnetka and Gatineau. Kubler lost the Winnetka final to top-seeded American Bradley Klahn but bounced back to win the Gatineau tournament without dropping a set. The result helped steer Kubler back inside the top 200 at 189 in the ATP rankings. Kubler was expected to contest the Challenger event in Granby, but withdrew due to a wrist injury.