Asian Games gold medallist Amit Panghal (52-kg) and four-time Asian Championships medallist Shiva Thapa (60-kg) were the other gold medal hopes who faced no hassles on their way to the final.
Mary Kom, gold medallist in the 48-kg category in the inaugural edition of India Open, took time to settle into the much-awaited bout as Zareen was the early aggressor. It was in the final round that the London Olympics bronze medallist found her strides and punched her way to a split verdict of 4-1 to set up a final showdown with Vanlal Duati, who beat Jyoti 3-2.
"Zareen is normally a boxer who doesn't like to come inside much and I am more of a counter boxer, so I used that to my advantage," said the Manipuri legend after her bout.
Siwach exuded confidence through his fiery flurry of punches against the accomplished Solanki to set up a final showdown with Panghal, who has won gold medals at the Asian Championships as well as the Strandja Cup this year.
Siwach, who won a bronze in the GeeBee boxing tournament in 2019, hopes to change the colour of his medal to gold in his first meeting with Panghal in any competitive event.
"I have beaten Solanki before and I was full of confidence that I would be able to beat him today as well," Siwach said after his win.
"Amit (Panghal) has improved a lot, but this is my big chance to show my prowess at a major competition at the senior level. This will be my first meeting with him in any competitive event and I hope to give my best," added the rising star.
A year after losing in the semifinals, 25-year-old Shiva Thapa rode on vociferous support to set up a revenge match with defending 60-kg champion Manish Kaushik.
Thapa, who came on the back of a bronze in the Asian Championships, did not take much time to assert his supremacy over Poland's D. Krystian Sczepanski whom he demolished 5-0. Kaushik, meanwhile, thumped Ankit 5-0 in his semifinal bout.
"My opponent was getting tired so I tried to put some false punches to make him more tired. I am glad the strategy worked," said Thapa after his victory.
Meanwhile, former World Championships bronze medallist Gaurav Bidhuri was the big Indian hope to lose out on a place in the final. Bidhuri was beaten 0-5 by Thailand's former Asian champion Chatchai Decha Butdee and had to settle for the bronze.
Asian Championships silver medallist Deepak (49-kg) did not even have to enter the ring to confirm his final berth as he got a walkover from Philippines' Carolo Cano Paalam. Kavinder Singh Bisht, also a silver medallist from the continental event, remained in the hunt for the 56-kg gold following a tight 4-1 win over compatriot Madan Lal.
Fresh from winning his maiden medal in the Asian Championships, Ashish Kumar (75-kg) will now target the gold after edging past Thailand's Aphisit Khankhokkruea 4-1. In the final, he will meet Eumir Felix Delos Santos of Philippines who knocked out Manjeet Panghal.
In the women's section, 2012 world champion Josie Gabuco of Philippines used her experience to dismiss the challenge of India's Kalavani 5-0 in the 48-kg category, while Monika prevailed over Manju Rani 4-1.
( With inputs from IANS )