Bajrang started with a closely-fought first round bout against Allen Rutherford of the US, which he ended up winning 5-4. He then faced Rutherford's compatriot Joseph Christopher McKenna in the quarterfinal and won 4-2.
He then beat Ukraine's Vasyl Shuptar 6-4 to assure himself of a spot in the final where he will face American Jordan Michael Oliver later on Saturday night.
Bajrang was, however, the only Indian wrestler to be assured of a medal with Jitender (74kg) and Deepak Punia (86kg) being knocked out earlier in the day.
Ravi Kumar Dahiya, who is competing in the 61kg instead of his usual 57kg category, beat Moldova's Alexandru Chirtoaca in the first round and Kazakhstan's Nurislam Sanayev in the second. He will face Nurbolat Abdualiyevof Kazakhstan later in the day.
Deepak, who is the reigning junior World Champion and won silver at the senior World Championships last year, crashed out in the first round with a 1-11 loss to Puerto Rico's than Adrian Ramos.
Jitender beat Ukraine's Denys Pavlov 10-1 in the first round before losing 0-4 to Turkey's Soner Demirtas in the quarters.
On Friday, Vinesh had won gold after beating Ecuador's Luisa Elizabeth Valverde 4-0. She beat China's Lannuan Luo (15-5) and Qianyu Pang (4-2) in the quarterfinal and semifinal, respectively. Anshu Malik (18) settled for silver in the 87kg category.
( With inputs from IANS )