The reigning 100m world champion is the man to beat in the event at the Lausanne IAAF Diamond League meet, which also features Noah Lyles and a triple jump Yulimar Rojas-Caterine Ibarguen showdown.
Justin Gatlin has said next season will be his last.
Speaking to BBC journalist Ade Adedoyin at the 2019 IAAF Diamond League meet in Lausanne, Switzerland, the 37-year-old sprinter said he aims to win gold at Tokyo 2020 as his final act in athletics.
“I want to leave on an Olympic cycle. My goal is to get to 2020 and get on top of that podium. If it ends well, if it doesn’t, I want to be able to leave my spikes on the track and say I am done,” Gatlin is reported to have said.
While Gatlin did defeat Usain Bolt in the 2017 IAAF World Championships in London - Bolt's last ever official individual race - the USA sprinter is determined to end his career with another Olympic gold medal.
On 1 July Gatlin proved he's still seriously fast, clocking 9.87s at the Prefontaine Classic in Stanford, California, only 0.06 seconds behind winner Christian Coleman.
"I was not really surprised by my good performance at Stamford - Gatlin said - I was trying to put a race pattern together after injury there, and to put on a good show for audience as I don't get to race for US audience very often."
"Getting older or age doesn't change much about training in the run up to Doha - he added - I like where competition in sprints currently stands now. There is no clear favourite always, and you have to wait to see who the winner is, which I like a lot."
At the IAAF Diamond League meet in Lausanne, which runs from 4 to 5 July, Gatlin is clear favourite to win the 100 metres discipline as he is the only sprinter in the field to have run a sub-ten second 100m.
With no Christian Coleman, Noah Lyles, or Michael Norman on the starting list, the race should belong to him.
Noah Lyles is taking part in the 200m and is keen to re-assert himself as the fastest man over this distance after he was narrowly defeated in Rome by fellow U.S. rising star Michael Norman, who ran the 200 in 19.69sec.
Lyles is the defending champion, winning the Lausanne 200m in 19.69s last year.
The 21-year-old will race to prove a point but he's up against a loaded field with three other men who have won at IAAF Diamond League meets this year: world champion Ramil Guliyev, Olympic silver medallist Andre De Grasse and Canada’s Aaron Brown.
There's another fascinating duel afoot in the women's triple jump in Lausanne.
This Colombia vs Venezuela battle of the neighbours always gets pulses racing.
But there is rivalry full respect and admiration.
Ibarguen was named IAAF Female Athlete of the year after a dominant 2018, where she won both Diamond League long and triple jump finals, but Rojas only competed once, and won, retaining her world indoor title in Birmingham.
Colombian Ibarguen began 2019 the way she left off in 2018, winning the Oslo Diamond League triple jump with 14.79m.
Then one week later Rojas opened her outdoor season with a Venezuelan record of 15.06m: the longest jump the world has seen since the Rio Olympic Games.
Ibarguen has tasted victory in 20 of her 23 competitions over the past three years, but all three of those losses came with Venezuela's Rojas finishing ahead of the Colombian.
There could be a shock in store too with 2012 Olympic champion Olga Rypakova, promising Cuban Liadagmis Povea, European indoor champion Anna Peleteiro and Jamaican duo Shanieka Ricketts and Kimberly Williams also in the line-up.