David Rudisha showed the rest of the world that it will take an extraordinary effort to wrestle the Olympic title away from him as the defending champion posted the fastest time from the morning’s seven heats, clocking 1:45.09 almost without breaking sweat.
Rudisha made qualifying for Saturday’s semi-finals look easy after he moved to the front in heat three after 200 metres and was never headed.
He passed the bell in 52.36 and then surged again with 150 metres to shake out the cobwebs and shake off anybody impertinent enough to challenge him at this stage in the competition.
South Africa’s Rynardt van Rensburg and Great Britain’s Michael Rimmer followed him home and to take the automatic qualifying spots and the pace was quick enough down the field that 2016 US champion Clayton Murphy was towed through as one of the fastest non-automatic qualifiers.
Heat one saw another US runner qualify as Brian Berian head to the front when the runners broke for the inside and he passed 400m in 50.78.
Berian kept the pace quick and held the lead until he was passed 70 metres from home by Djibouti’s Ayanleh Souleiman and then Bosnia’s 2015 world championships bronze medallist Amel Tuka, but the US runner hung onto secure the third automatic qualifying spot as Souleiman won in 1:45.48, the second fastest time in the heats.
Poland’s two-time European champion Adam Kszczot was an impressive winner of the second heat, going through the gears from 200 metres out and moving quickly clear of the chasing pack.
He had the luxury of being able to ease off 20 metres from the line, which he passed in 1:45.83 as Kenya’s Ferguson Rotich and Puerto Rico’s Andres Arroyo won the five-way battle behind him for the other two automatic qualifying spots.
The fourth heat saw this year’s Kenyan champion Alfred Kipketer hit the bell in 53.52 and dominate proceedings over the second lap.
Kipketer won in1:46.61 and at this early stage in the competition seems like Rudisha’s closest rival for the gold medal. He had few problems holding off fellow automatic qualifiers, Denamrks Andraes Bubbe and Algeria’s unheralded Yassine Hethat, down the home straight.
However, this heat saw the elimination not only of Vazquez but of USA’s Charles Jock and Great Britain’s recent European Championships bronze medals Elliott Giles.
Heat five saw Spain’s Kevin Lopez lead the field around the first lap in a near-pedestrian 56.41.
Seven runners came into the home straight still in contention for the three automatic qualifying spots but London 2012 Olympic Games 1500m champion Taoufik Makhloufi should his renowned speed to come through over the final 40 metres and win in 1:49.17.
He was followed home by Morocco’s Mustafa Smaili and Italy’s Giordano Benedetti. However, London silver medallist Nijel Amos found himself lacking a turn of speed and drifted back to seventh.
Canada’s Brandon McBride front ran the sixth heat, passing through 400m in 51.83 before winning by five metres in 1:45.99.
Poland’s 2016 European silver medallist Marcin Lewandowski was in trouble with 200 metres to go and lying back in fourth with a lot of ground to make up but had the finishing speed to come through for second as Ireland’s Mark English produced a quick finish to move up several places and take third.
The field in the final heat seemed content to sit on the tail of Pierre-Ambroise Bosse, who towed them through the first lap in 55.99, and nobody had any response when the Frenchman accelerated with 150 metres to go to win in 1:48.12.
Mohammed Aman clinched second place behind Bosse with a spirited finish over the final 50 metres but looks somewhat short of the form that took him to world indoor and outdoor titles in 2013 while Algeria’s Amine Belferar exceeded some expectations and finished third.
Phil Minshull for the IAAF