Despite improving his lifetime best to 6.06m this season, a height only three others have ever cleared, defending champion Sam Kendricks has his work cut out for him in an event that will be among the key highlights at the IAAF World Athletics Championships Doha 2019.
Five of the entrants have career bests at 6.00m or better; three, including Kendricks, have scaled that height this year.
The precocious Armand Duplantis, not yet 20, was the first, clearing 6.00m on 11 May to end his abbreviated collegiate career as the NCAA record holder. Poland's Piotr Lisek was next, topping 6.02m in Monaco. Then came Kendricks, whose 6.06m second-attempt clearance at the US Championships in Des Moines came despite the fact that he didn't need to compete at such a high intensity, given that his team slot was already secured as the defending champion. But he did anyway, dropping back to earth as the North American record-holder with the highest outdoor vault since Sergey Bubka topped 6.14m on 31 July 1994, when Kendricks hadn't yet blown out the candles on his second birthday cake.
That was hardly a one-off for Kendricks, who has also scaled 5.95m and 6.00m this season while collecting victories in 11 of his 16 outdoor competitions. The 27-year-old has remained stunningly consistent in recent years, a stretch that includes an undefeated record indoors and out in 2017.
But retaining a world title in the pole vault is a near-impossible chore. Only Bubka, who won a jaw-dropping six titles between 1983 and 1997 – at each of the first six editions of the World Championships – has managed to win the crown more than once.
Lisek's massive vault in Monaco wasn't a one-off, either. That came just one week after he topped 6.01m in Lausanne, his first jaunt into rarified six-metre air. Those were two of his higher profile 11 victories in 23 outdoor competitions this season for the 27-year-old who jumped to bronze in 2015 and silver in 2017.
For his part, Duplantis also has a pair of 6.00m clearances to his credit, topping that height for the second time this year at the Sweden-Finland match on 24 August. He's won eight of his 14 outdoor competitions including his last two, in Berlin’s ISTAF and the Europe-USA match in Minsk, topping 5.80m and 5.85m.
The field also includes career six-metre men Thiago Braz, the Olympic champion, and Renaud Lavillenie of France, who has won every major title available to him except that of world champion outdoors. Lavillenie topped a season's best of 5.85m to take the national title, his 16th overall, on 28 July, while Braz, who has struggled with consistency since his emotional Rio triumph, cleared 5.92m in Monaco, equalling the third best jump of his career.
Others to watch include Lisek's teammate Pawel Wojciechowski, the 2011 world champion, who has topped 5.87m, and rising US star Cole Walsh, who has improved to 5.83m.
Raphael Holzdeppe of Germany, who vaulted to gold in 2013 and silver two years later, is also entered.
Bob Ramsak for the IAAF