A slow first heat, won by Kenyan Mercy Cherono, gave the also-rans who followed in heat two a time target to aim for and a good pace ensured all except Georgian Giuli Dekanadze, who was lapped by the field, went through.
Defar, world champion in 2007 but bronze medallist in each of the last two editions, said she had “prepared well” for Moscow, where her task has been made easier with team mate Tirunesh Dibaba, winner of the 10,000 metres, not bidding for a distance double.
“I am ready for the final,” Defar said. “It will be a battle between Kenya and Ethiopia again.”
Kenya’s Asbel Kiprop and Silas Kiplagat battled it out for 1,500 metres gold and silver two years ago in Daegu, South Korea, and both eased into Friday’s semi-finals with heat wins.
Kiprop is favourite to defend his title after clocking a stunning 3:27.72 in Monaco on July 19, putting him fourth on the all-time list, but he guarded against complacency.
“I never under-estimate anyone,” the tall Kenyan said.
In women’s hammer qualifying Germany’s Betty Heidler was a notable casualty, the 2007 world champion and twice silver medallist putting her failure to reach Friday’s final down to “technical problems”.