The Asian Championships silver-medallist, who has won two rounds so far in the event, will now be up against the winner of the clash between Canadian Custio Clayton and Northern Ireland's Steven Donnelly.
The 21-year-old, a protege of former Commonwealth Games gold-medallist Akhil Kumar, was declared the winner after his rival, Daniel Lewis of Australia, failed to get the doctor's clearance to fight due to a cut above his eye sustained during the pre-quarterfinals.
"I never went in with any kind of targets as such. I just wanted to perform well. All these thoughts of medal and targets were set by Akhil bhaiyya. He had faith in me and I am glad that I repaid that faith. I am glad that I could do the country proud," Mandeep told PTI.
"It is the biggest moment of my career because my mentor, Akhil bhaiyya, left his training midway on hearing this news. I feel proud to have made him proud," added the boxer.
"I would now just watch the bout later in the evening and then make my strategies accordingly. I have trained very hard and I am feeling very good about my body right now. I hope I can go the distance," said the boxer.
Meanwhile, Akhil, congratulated his protege.
"I always knew he had it in him to make it at the top level. I believe in his skill and I see a lot of myself in his playing style as well. I am thrilled for him and I pray to God that this is the start of many more big things to come for him.
Besides, Mandeep is also being supported by Anglian Medal Hunt.