The winning marks in three of the four heats were remarkably close, as Wilfried Bungei of Kenya (1:48.17) recorded the fastest time in winning the last section over Botswanan Glody Dube (1:48.48).
His teammate, Joseph Mutua had already come home first (1:48.26) in an earlier heat, in which the other automatic qualifying spot was claimed by Holland’s Bram Som (1:48.40).
The gold medal favourite in the event, Denmark’s Wilson Kipketer, broke open a leisurely opening section at the halfway mark and coasted to a 1:48.47, ahead of American David Krummenacker (1:48.66).
The only notable casualty came in the day’s slowest section, won by Spain’s Antonio Reina (1:49.38) ahead of Czech runner Roman Oravec (1:49.66). South African Hezekiel Sepeng, the Atlanta silver medallist and a prime contender for a medal, originally finished second, but was disqualified for a lane infringement.