[2] On 30 January 2018, Tomic withdrew from the competition after three days, owing to feeling uncomfortable and depressed, thus making him one of the shortest-lived contestants on the show globally.

He also claimed he would achieve these goals by attaining the serve of Goran Ivanišević, the mind of Pete Sampras, the groundstrokes of Roger Federer and the heart of Lleyton Hewitt.

Playing his first singles event on the ITF Junior Circuit in 2006, he qualified for the Sunsmart 18 and Under Canterbury Championships in New Zealand and went on to win the title at 13 years of age, defeating Oh Dae-soung of Korea in the final.

He would then travel to Italy where he compiled an undefeated record in the Junior Davis Cup and lead Australia to victory in the final against Argentina with teammates Mark Verryth and Alex Sanders.

At the 2008 US Open, Tomic lost in the first round of the boys' singles to qualifier Devin Britton of the United States in three sets, who would go on to lose in the final.

In December, Tomic competed at a F12 tournament in Australia where he defeated fellow Australian James O'Brien in the first round before controversially walking off court whilst down a set and 3–1 against Marinko Matosevic in his next match.

[34] Following the defeat, Tomic decided to return to the junior tour to contest the Grand Slam tournaments and reached the quarterfinals of the French Open.

He defeated Julien Benneteau, Japanese qualifier Tatsuma Ito and Denis Istomin to reach his first ATP semifinal where he lost in straight sets to world No.

Tomic began his grass court season at the 2012 Gerry Weber Open where he retired against wildcard and eventual champion Tommy Haas in the first round whilst down 5–2.

The following week, Tomic reached the third round of the Cincinnati Masters, defeating Americans Ryan Harrison and Brian Baker en route, before losing to the world No.

At the Eastbourne International, Tomic defeated James Ward and Julien Benneteau en route to the quarterfinals where he lost to Gilles Simon in straight sets.

This was the first of five consecutive main-draw losses, which included losing to Jérémy Chardy in Shanghai, Jack Sock in Stockholm, Mikhail Youzhny in Valencia and Feliciano López in Paris to close out his 2013 season.

After undergoing two hip surgeries, Tomic returned to the tour to play at Miami,[65] where he lost in the first round against Jarkko Nieminen in 28 minutes, winning just one game.

Tomic began his grass-court season at Eastbourne where he defeated Tim Smyczek in the first round before losing to Radek Štěpánek in straight set tie-breaks.

In the quarterfinals, he defeated fourth seed Vasek Pospisil in straight sets, to advance to the semifinals where he emerged victorious in a tight three-set clash over Víctor Estrella Burgos.

At the 2014 Stockholm Open, Tomic defeated Patrik Rosenholm, Kevin Anderson and Fernando Verdasco; in the semifinal, he lost to Grigor Dimitrov.

Tomic began his grass-court season at the 2015 MercedesCup where he defeated Jan-Lennard Struff and Tommy Haas to reach the quarterfinals where he lost to former world No.

Tomic's then played at the 2015 Western & Southern Open where he defeated Sergiy Stakhovsky in the first round, he then lost to eventual semi-finalist Alexandr Dolgopolov.

His final tournament of the year was the Paris Masters where he defeated Fabio Fognini before losing to eventual semifinalist Stan Wawrinka in the second round.

He breezed through to the fourth round with defeats over Denis Istomin, Simone Bolelli and John Millman before losing in straight sets to eventual runner up and second seed Andy Murray.

At the Australian Open, Tomic defeated Thomaz Bellucci and Víctor Estrella Burgos to reach the third round where he lost to Dan Evans in straight sets.

Tomic quit the competition after three days, proclaiming a desire to return to tennis as the primary reason, in turn having one of the shortest times on the show globally.

Following the French Open, Tomic qualified for the Rosmalen Grass Court Championships in the Netherlands, where he made a surprise run to the semi-finals, losing to eventual champion Richard Gasquet in three sets.

[80] Tomic defeated fellow lucky loser Hubert Hurkacz in the first round to earn his first Grand Slam main-draw win since the 2017 Australian Open.

There, he defeated 14th seed Jozef Kovalík, Tristan Schoolkate and John-Patrick Smith to qualify for his first Grand Slam tournament in close to two years at the Australian Open.

[84] Tomic's next tournament was the Monterrey Challenger in March, where he recorded his first match win at any level since the qualifying rounds at 2021 Wimbledon by beating fourth seed Cedrik-Marcel Stebe in straight sets.

There, he reached his first Challenger quarterfinal since 2018 after defeating Juan Pablo Ficovich and upsetting second seed Emilio Gómez while saving two match points.

Prior to the commencement of the 2012 ATP season, Tomic and Lleyton Hewitt both committed to the Davis Cup team for all ties in a bid to re-enter the world group.

[99] In November 2012, Tomic pleaded guilty in court to failing to stop for police in his orange BMW M3 and was fined $750, as well as being put on a 12-month good-behaviour bond.

During his third round press conference, following his loss to top seed Novak Djokovic at the 2015 Wimbledon Championships, Tomic ranted against Tennis Australia, namely Craig Tiley, Pat Rafter and Steve Healy.