2010–2012: Career beginnings Whittington made his first singles appearance in April 2010 at the Australian F3 where he lost in round 1 to Brendan Moore. Throughout 2010/11, Whittington played mostly on the ITF circuits across Australia and the USA where he reached two quarter finals in singles. In 2011, Whittington began partnering
Luke Saville in doubles. The pair won back-to-back ITF doubles titles in November. The pair were given a wild card into the
2012 Australian Open Men's doubles. They lost in round 1. In March 2012, Whittington began partnering
Alex Bolt; the pair won three ITF doubles titles before June. Whittington made his first appearance in the singles main draw of an
ATP Challenger Tour at
Caloundra in February 2012, losing narrowly in round 1. The remainder of 2012 was spent on the ITF Circuit across Australia and Europe and he reached two semi-finals.
2013–2014: Doubles success In January 2013, Whittington was given a wild card into the
Burnie Challenger where he reached the quarter-finals, before playing ITF tour across USA and Europe. In April, Whittington reached his first final in Greece. He lost to
Dimitar Kuzmanov in straight sets. He returned to Australia in September 2013 and lost in the final of the Australia F6 to Adam Feeney, before winning his first single title the following week at the F7 against
Alex Bolt. Following the win, he told Tennis Australia "I’ve never felt like that before, I still feel like I’m out there playing." In November 2013, he won his second ITF title in Cambodia against Gavin van Peperzeel. In doubles, Whittington played with a number of partners throughout 2013 but re-joined Alex Bolt in September and commenced a successful doubles run. The pair won three consecutive ITF doubles titles in Australia and in October, the pair reached their first
Challenger final at the
Melbourne Challenger, losing to
Thanasi Kokkinakis and
Benjamin Mitchell. In January 2014, Whittington lost in the first round of qualifying for the
2014 Brisbane International and
2014 Australian Open. Whittington and Bolt were given wild cards into the
Men's doubles. The pair defeated the number 3 seeds
David Marrero and
Fernando Verdasco in round two, ultimately losing at the quarter-final stage to number 8 seed
Daniel Nestor and
Nenad Zimonjić. The match was played on
Rod Laver Arena; the pair's first appearance on centre court. The pair then made a series of semi-finals across Australia circuit before winning their first
Challenger title in
Anning in May. This increased Whittington's double ranking to within the world's top 100. In June, Whittington and Bolt qualified for the
2014 Wimbledon Championships – Men's doubles, this was the pair's first appearance at Wimbledon. They lost in round 1 to
Feliciano López and
Jürgen Melzer. In August, Whittington lost in the final of the Chinese Taipei F1 before returning to Australia playing in ITF and Challenger circuit. By November 2014, Whittington had reached his twentieth doubles final. Whittington ended 2014 with a singles ranking of 525 and doubles ranking of 109.
2015–2016: Focus on singles and ATP World Tour debut In January 2015, Whittington and Bolt made the final of the
Onkaparinga Challenger, before reaching the third round of the
Men's doubles. Throughout the rest of 2015, Whittington began focussing on singles matches on the ATP Challenger tour, with limited success. Whittington commenced 2016 at the
Happy Valley Challenger, qualifying for and reaching the semi-final. This was his best singles performance to date at this level. Whittington then played the
Canberra and
Launceston challenger events before winning his third and fourth ITF singles title in Mornington in March. He played in
Nanjing,
Anning and
Bangkok challenger events before winning his fifth ITF title in Guam in May. In June, Whittington won three ITF titles in three weeks in Hong Kong. In July, Whittington was seeded for the first time in a Challenger Event at
Gimcheon and reached his first final against Max Purcell. This was followed up by a semi final result at
Lexington Challenger and quarter final result at
Granby. Whittington increased his singles ranking inside the top 200 for the first time. In September, Whittington contended the
US Open for the first time, losing in round 1 of
qualifying to
João Souza. Whittington then qualified for the main draw of an
ATP World Tour for the first time in
Shenzhen. In his ATP debut, he saved four match points against
Luca Vanni, eventually winning 2–6, 7–6, 6–2 in two hours and 20 minutes. He lost in round 2 to
Richard Gasquet. Whittington ended the year playing challenger events in Vietnam and China. Whittington ended 2016 with a career high singles ranking of 170 and a doubles ranking of 312.
2017: First Grand Slam appearance On 2 January 2017, Tennis Australia awarded Whittington a wild card into the
2017 Australian Open. This was Whittington's first singles appearance in a grand slam. He defeated
Adam Pavlásek in 4 sets in round 1, before losing to
Ivo Karlović in round 2. Whittington partnered
Marc Polmans in the
2017 Australian Open – Men's doubles, where they reached the semi-finals. Whittington played on the challenger tour before heading to USA in March, where he lost in qualifying for both
Indian Wells and
Miami Masters. At the
French Open Whittington lost in round 1 of qualifying. In June, Whittington entered the qualifying for Wimbledon. In the first round of qualifying, he recovered from a 1–4 deficit in the final set, saving break points in the sixth game against
Stéphane Robert of France, to prevail 3–6, 7–5, 6–4. In R2 of Qualifying he won from a set down again, winning 6–7, 6–4, 6–4 against
Tim Smyczek before qualifying for
Wimbledon for the first time 4–6, 2–6, 7–6(7), 7–6(3), 6–0. Whittington saved two match points in the third set tie-break at 4–6 after coming from 2–5 down in that same tie-break against
Denis Kudla. Whittington gallantly went down to
Thiago Monteiro in R1, saving match points against his serve at 4–5 in the fourth set before losing that set and the match in a tie-break. ==Personal life==