Rohan kept a cool head to smash unbeaten 79 runs, studded with seven hits to the fence in a tense situation with the team losing nine wickets.
In a do-or-die situation, the junior Gavaskar hit Sahabuddin over long-on to run for the required two runs, thus ensuring valuable four points for his side.
When Rohan arrived at the crease after the departure of A A Jhunjhunwala, East Zone was well placed with 118 runs for the loss of three wickets in 18.1 overs. However, thereafter Mihir Tiwary, soon lost his wicket at 139, but captain Deep Dasgupta provided wonderful support to Rohan and helped his side cross the 200-run mark.
Just when everything was looking comfortable for East Zone, with the team's total on 216 and Deep's personal score on 39, he was sent back to the pavilion by Ojha.
All of sudden the East Zone side continued to loose batsmen at regular intervals. But Rohan kept his end intact to steer his side to victory.
Chasing the target of 271 runs to win, the opening pair of W P Saha, who made 15, and P Aziz, who made 56 runs in just 37 balls, gave a solid start to their side.
For South Zone K S Sahabuddin, D Kalyankrishna and P Ojha grabbed two wickets each.
Earlier, powered by Swapnil Asnodkar's ton, South Zone set up a tough target of 271 runs in 50 overs for East Zone.
Swapnil's run-a-ball knock of 107 was well supported by skipper V V S Laxman (35). Swapnil and Laxman stitched together 89 runs for the second wicket in 15.4 overs.
East Zone skipper Deep Das Gupta felt his decision to field backfiring as South Zone openers Swapnil and Barrington Rowland made an electrifying start with some lusty hits. Another good partnership of 73 runs between Swapnil and Venugopal Rao in 14 overs set the South Zone on way to a big score.
However, when the total was 194 runs, Venugopal Rao gave a simple return catch to S Singh with his individual score reading 30.
South Zone received another jolt when Swapnil ballooned a sweepshot off Abhishek Jhunjhunwala delivery at square leg which was gladly accepted by Divakar. In his 107-run knock, Swapnil had 14 hits to the fence.
At this point, South Zone, eyeing the magical figure of 300 runs, lost some quick wickets to finally end up at 270 runs for the loss of eight wickets in 50 overs.
For East zone, Ranadeb Bose and S Singh took two wickets each while S S Paul, M Diwakar and Jhunjhunwala took one wicket each.
South Zone 270 for 8 in 50 overs (Swapnil Asnodkar 107, VVS Laxman 35, Venu 30, Arjun Yadav 25; Sunny Singh 2 for 47, Randeb Bose 2 for 50, Abhishek Jhunjhunwala 1 for 39) lost to East Zone 271 for 9 in 50 overs (Rohan Gavaskar 79 n o, P Aziz 56, Deep Dasgupta 39, A Jhunjhunwala 28; Pragyan Ojha 2 for 40, Shahbuddin 2 for 59, Kalyankrishna 2 for 61) by one wicket.