India's 800m runner Tintu Luka qualified for the semifinals after coming third in the heats with a time of 2:01.75, beating Morocco's Malika Akkaoui by just 0.03 seconds.
Russia's Mariya Savinova finished first with 2:01.56, followed by US runner Alice Schmidt who clocked 2:01.65.
The 23-year-old Luka found herself boxed in between the taller runners, but gave it her all in the last 30 metres to qualify for the semis.
Tintu, who trains at PT Usha's academy, will now compete in the semis on Thursday at 12 AM IST (midnight).
The runner's season best is 2:01.09 and she will have to at least equal or beat that to stand a chance of qualifying for the finals.
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