Between the two of them, German Robert Harting and Piotr Malachowski of Poland have captured the past four world discus titles. Attempting to extend that supremacy will be one of the key story lines in London, especially as it'll be challenged by a pair of much younger upstarts.
Harting's experience at the World Championships dates back a decade when he first struck surprise silver in Osaka. That 2007 success paved the way for three successive titles that came wrapped in some of the most entertaining victory celebrations in the history of these championships. A fourth title for the 32-year-old will leave him just one shy of Lars Reidel's record five.
He's not quite the same thrower he was half a decade ago, a period in which he also captured back-to-back European titles in 2012 and 2014 along with Olympic gold in 2012. That year he also produced his best two throws, 70.66m and 70.31m.
He was sidelined in 2015 and last year didn't advance from the qualifying round at the Olympic Games in Rio, a competition ultimately won by his younger brother Christoph.
While low key, he's riding better momentum en route to his return to the London Stadium, winning three of his five 2017 competitions including the past two: the European Team Championships with a 66.30m season's best and his national championship with 65.65m, an effort that came during a period of heavy training. That bodes well.
Malachowski's World Championships history also dates back to 2007 where he reached the final as a 24-year-old, finishing 12th. He took Olympic silver the following year and silver again at the 2009 World Championships where he and Harting engaged in a fierce round-by-round battle with the German finally prevailing with a 69.43m throw in the final round.
After a disappointing ninth place finish in 2011, Malachowski took another silver in 2013, again second to Harting. In his fifth straight World Championships appearance, the Pole finally ascended to the top stop in Beijing two years ago.
After that decade-long struggle, he'll want to retain ownership of that perch for just a little bit longer. A season's best 67.68m in Cetniewo on 29 July indicated that he too is rounding into shape at the right time. Notable as well is that with a 71.84m lifetime best from 2013, the Pole sits fifth on the world all-time list.
Leading the new generation's charge is Daniel Stahl, the towering Swede whose massive 71.29m effort in Sollentuna on 29 June landed him into the No.9 position all time. Stahl, 24, has been fairly consistent, too, winning 12 of 16 competitions this season, including the Oslo and London IAAF Diamond League fixtures. In his most recent outing, he reached 67.26m on 25 July in Karlstad.
Jamaican Fedrick Dacres is also in the midst of a breakout season. The 2011 world U18 and 2012 world U20 champion, Dacres, now 23, has lived up admirably to that early career success this season, spending much of it atop the world list after his 68.67m and 68.11m national records in January and February. More recently, he took home a victory at the Stockholm stop of the IAAF Diamond League on 18 June.
Others expected to battle for the medal grab include Andrius Gudzius of Lithuania and Belgium's Philip Milanov. Gudzius, an Olympic finalist last year, has bettered 68 metres three times this year, topped by a 68.61m career best. Milanov, the silver medallist two years ago, reached a season's best of 67.05m in the Stockholm leg of the IAAF Diamond League and finished third at the series' Oslo and London legs.
With season's bests of 66.73m, 66.61, and 66.52m respectively, Pole Robert Urbanek, Andrew Evans of the US and Lukas Weisshaidinger could also mount bids for a podium finish.
Bob Ramsak for the IAAF