After the defeats of fourth seed Shiva Thapa (56kg) and sixth seed Manoj Kumar in the afternoon, Vikash Malik (60kg) and Sumit Sangwan (81kg) also lost their quarter-final bouts in the evening session.
Satish Kumar (+91kg), meanwhile, was declared medically unfit to fight after sustaining a cut above his right eye on Tuesday in the pre-quarters.
While fourth seed Shiva went down to Azerbaijan's Javid Chalabiyev, sixth seed Manoj was defeated by Cuba's Yasnier Lopez. Both the boxers lost 0-3.
In the second session, Vikash lost 0-3 to fourth seeded Brazillian Robson Conceicao, a Pan-American Games silver-medallist.
Sumit (81kg) went down to world No 1 and top seed Adilbek Niyazymbetov of Kazakhstan.
In the evening session, Vikash started the proceedings for India and found himself struggling with technique despite showing a lot of heart to fight against the supremely fit Brazilian.
Robson was aggressive from the opening second itself and used his better reach to good effect by being viciously precise with his uppercuts and body blows which forced Vikash into a shell guard.
The Indian ended up getting standing eight counts in each of three rounds due to the cracking blows of Robson even though he showed tremendous endurance to withstand the assault.
Vikash's wild atempts at hitting straight just did not connect powerfully enough to convince the judges, who were nonetheless liberal in giving him points in the second and third round for his sheer determination.
Sumit also failed to spring any surprise when he faced Olympic silver-medallist Niyazymbetov. Both the boxers chose to play the waiting game and counter-attack but none gave the other too many chances to capitalise.
There were hardly any punches exchanged between the two as they spent almost the entire 11 minutes getting a measure of each other.
Sumit, despite being taller and having better reach, failed to engage Niyazymbetov, who connected clearly in the few opportunities he got to be the clear winner at 3-0.
With this edition's campaign ending on a disappointing note, India's all-time medal tally at the World Championships remains just two.
Vijender Singh (75kg), who bowed out of the ongoing event in the second round, opened India's account in 2009 with a bronze medal.
In the next edition in Azerbaijan, Vikas Krishan (69kg) also grabbed a bronze medal.
Image: Vikash Malik
Photograph: IBF Media
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