The 26-year-old, the reigning Asian champion and national record holder, clocked her season's best of 2:00.95 to finish seventh in the first of the six heats to fail to qualify for the semifinals. Three top finishers in each of the six heats and the next six fastest timers qualify for the semifinals.
Luka, who has a personal best of 1:59.17 which she clocked in 2010, though got the consolation of crossing the Rio Olympics qualification time of 2:01.00.
Six runners ran past her in the last 200 meters as the Indian burnt herself out in a repeat scenario of so many of her races at the international stage.
Luka was also a bit unlucky as she was pitted in a more competitive heat as the three top finishers in heat numbers four and five clocked worse times than the Indian but they still advanced to the semifinals.
It was Tintu's second appearance in the World Championships. She was a semifinalist at Daegu, South Korea in 2011.