Resuming at the overnight score of 123 for 5, Central lost wickets at regular intervals as skipper Piyush Chawla emerged the team's top-scorer with a fine knock of 56.
In reply, South Zone were cruising along with captain Abhinav Mukund (61) and Baba Aparajith (35) at the crease when stumps were drawn for the day.
The hosts need to score just 73 more runs to take the first innings lead. Barring a collapse they should book a berth in the final.
In the morning session, overnight batsman Shalabh Srivastava (22) did not last too long and was trapped leg before by Malolan Rangarajan.
Chawla tried to hold fort but after a 42-run seventh-wicket partnership with Jalaj Saxena, he became spinner Pragyan Ojha's second victim in an overall wickets tally of 3 for 49.
Chawla's stay at the crease yielded four fours and three sixes.
The batsmen that followed him did not do much and Central Zone folded for 209.
Besides Ojha, Abhimanyu Mithun also grabbed a three-wicket haul, conceding merely 29 runs in his 14 overs.
In response, South made a good start, with Mukund and Akshath Reddy (16) putting on 44 runs for the opening wicket. Chawla broke the stand before Umesh Yadav accounted for Lokesh Rahul (11).
However, Mukund found a steady partner in Aparajith, who was patience personified in his 100-ball stay at the crease.
Mukund, on the other hand, struck five fours in his 195-ball knock.
Brief scores:
Central Zone: 209 all out in 85.4 overs (Piyush Chawla 56; Abhimanyu Mithun 3/29, Pragyan Ojha 3/49)
South Zone: 137 for two in 63 overs (Abhinav Mukund 61 batting; Umesh Yadav 1/36).
Unmukt Chand, Ian Dev shine for North Zone
Kochi: Young opener Unmukt Chand led the way with a patient century as North Zone posted a formidable 329 for two in their Duleep Trophy semi-final.
While the 20-year-old Chand scored 116 off 230 balls, Ian Dev Singh was unfortunate to miss a century by five runs due to a hamstring injury.
After only 17 overs were bowled on the opening day, Thursday, due to rain, the North Zone batsmen batted with purpose to get into a strong position after batting 112 overs at the Nehru stadium.
At stumps, Mandeep Singh and Rajat Paliwal were batting on 40 and 41, respectively.
Chand struck 17 fours and a six during his stay at the crease while Ian Dev, in his 180-ball knock, hit 11 fours and two sixes.
Resuming at 33 for no loss, North lost their first wicket when Ashok Dinda dismissed Jiwanjot Singh for 24 with the team score reading 50.
Then followed a big 198-run stand for the second wicket between Unmukt and 24-year-old Ian Dev, leaving the East Zone bowlers looking for answers.
The bowlers couldn't effect a breakthrough till Shahbaz Nadeem brought an end to Chand's tenure with his team well-placed at 248 for two.
Meanwhile, Ian Dev retired hurt just five short of a century.
Mandeep and Paliwal then added 81 runs for the third wicket as North finished the day without losing any more wicket.
Mandeep found the fence six times while Paliwal hit three boundary and a six.
Only Dinda and Nadeem could get their names on the wicket column.
Image: Abhinav Mukund
Photograph: Getty Images
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