Kerron Clement consolidated his status as the slight favourite for the men’s 400m hurdles when he clocked a season’s best of 48.26 to win the first semi-final on Tuesday.
Japan’s Keisuke Nozawa was the first to rise over the initial six barriers but Clement’s vast experience told during the second half of the race and the two-time world champion, running out in lane eight, held the lead coming into the home straight.
As Nozawa, in lane three, started to fade, Kenya's 2015 World Championships finalist Boniface Tumuti came through strongly to take the second automatic qualifying place in 48.85.
Sergio Fernandez also finished fast to take third in 48.87, finally getting the Spanish record after several near misses in recent weeks, and taking 0.13 off a mark which had stood since 1987. However, it was not quick enough to advance to the final.
Semi-final two saw Jamaica’s Annsert Whyte run an authoritative race from the gun to take 0.05 from his personal best with a win in 48.32.
Now 32, Javier Culson ran a well-timed race to come through strongly for second place in 48.46 as Turkey’s European champion Yasmani Copello looked to be having to work harder than expected throughout the race but hung on to take third in 48.61. He was followed home 0.03 later by Estonia’s Rasmus Magi, both men eventually getting through as non-automatic qualifiers.
The third semi-final witnessed as a surprise as Thomas Barr came down the home straight like a bullet to win in 48.39 – evoking memories that most athletics fans have only read about of Bob Tisdall’s 1932 Olympic win in this event for Ireland – and taking 0.25 off his own national record.
With a relatively raw technique but outstanding flat speed, Haron Koech – the brother of world champion Nicholas Bett – held the lead through the first eight hurdles and hung on to take second, setting his second personal best in as many races when crossing the line in 48.49.
USA’s Byron Robinson also finished well, as Norway’s Karston Warholm – who had challenged Koech for the lead between 200 and 300 metres – faded. Robinson's personal best of 48.65 in third was not quick enough by just 0.01 to progress as Warholm finished fourth in 48.81.
Phil Minshull for the IAAF