Noah Lyles (Men's 200m)
Bolt's astonishing 19.19 seconds in the German capital back in 2009 took the breath away and looked set to stand for generations. Anyone going quicker remains a long shot but, as Bolt himself proved by going under Michael Johnson's apparently unassailable 19.32, even the most celebrated records are there to be broken.
"I have a strong chance of winning and I also have a strong chance of trying to break some records," American sensation Noah Lyles told BBC Sport when reflecting upon a superb 2019 to date. "I might not get another chance like this again because I plan to be doubling after this."
Lyles, 22, will only compete in the 200 meters in Doha, having broken Bolt's Paris Diamond League meeting record last month in a time of 19.65. His 19.50 in Lausanne in July is the fourth-fastest time in history. Gold looks assured - the question is just how impressive that gold might be.
Karsten Warholm (Men's 400m hurdles)
In Zurich last month, Norway's Karsten Warholm ran the second fastest 400m hurdles of all time, powering home in 46.92. However, gold is far from a formality for the world's leading performer.
Warholm was pushed all the way to the line by Rai Benjamin and the American's time of 46.98 made it the first race ever to have two men go under 47 seconds.
Consider the fact that Qatar's Abderrahman Samba also has a 46.98 on his record and Kevin Young's celebrated mark of 46.78 has never felt more under threat since it was set way back in 1992.
Dalilah Muhammad (Women's 400m hurdles)
Unlike the other competitors on this list, Dalilah Muhammad has already scaled the mountain.
The Olympic champion won the USA Track and Field title in Iowa this year with a blistering time of 52.20, shaving 0.14 off Yuliya Pechonkina's 2003 world record.
The 29-year-old will now aim to repeat those heroics on this year's biggest stage.
Yulimar Rojas (Women's triple jump)
Defending the world title she won in London two years ago, Venezuela's Yulimar Rojas heads to Doha peaking at just the right time.
At the start of this month, she leapt 15 metres 41 centimetres in Andujar, just 9cm shy of Inessa Kravets' 1995 record, which was established on the way to world championship glory.
Repeating that piece of history would round off a stellar year for Rojas, who put an injury-ravaged 2018 behind her to triumph at the Pan American Games in Lima.
Juan Miguel Echevarria (Men's long jump)
On the same Zurich evening Warholm and Benjamin went toe to toe, Juan Miguel Echevarria obliterated the competition in the long jump.
His 8.65m was the longest in the world this year and broke the Diamond League record. The Cuban star also thrilled a home crowd in Havana with a huge 8.92m in March, although his wind-assisted effort was not eligible for record purposes.
The latter leap was close to Mike Powell's imperious world record of 8.95m, which remains unlikely to be challenged in settled conditions.