Soparkar, a resident of Thane who trailed former Asian snooker champion Merchant 2-5, surged to a 6-5 lead with a stunning recovery, before snatching a nail-biting win on a day of close encounters.
In other ties that went down to the wire, Mahesh Jagdale of Elphinstone Cricket Club beat qualifier Divesh Gangwani of Juhu Vile Parle Gymkhana and Arun Madhu of Tamil Nadu overcame J S Dawer of host club NSCI.
The other significant winners were Hasan Badami and Nikhil Ootam of CCI, Ishpreet Singh Chadha and Rishabh Thakkar of Khar Gymkhana, Aditya Agrawal of PJ Hindu Gymkhana, Rovin D'Souza of Railways and qualifiers Avinash Kumar of Delhi and Arun Madhu of Tamil Nadu.
Results (all from Mumbai unless stated otherwise): Hasan Badami bt Sunil Jain 7-4; Nikhil Ootam bt Rahul Bhatnagar 7-3; Mahesh Jagdale bt Divesh Gangwani 7-6; Ishpreet Singh Chadha bt Ankit Ravasa 7-0; Abhishek Soparkar (Thane) bt Yasin Merchant 7-6; Avinash Kumar (Delhi) bt Dhanraj Minawalla 7-4; Arun Kumar (Thane) bt Ish Bawa 7-5; Arun Madhu (TN) bt J S Dawer 7-6; Prabdeep Singh bt Jaiveer Dhingra 7-5; Aditya Agrawal bt Ronnie Daruwalla 7-3; Rishabh Thakkar bt Nitesh Madan (Rlys) 7-3; Rovin D'Souza (Rlys) bt Shekhar Surve 7-1.