Considering Tamil Nadu were bowled out for 121 in the first innings and conceded a lead of 52 runs, it was a brilliant fightback by Abhinav Mukund's boys.
Chasing a target of 401, Railways starting the day on 108 for no loss, were all-out for 226 in 82.2 overs as the last five wickets fell for only for 4 runs.
Off-spinner Malolan Rangarajan had best figures of 4/37 while seamers Jagannathan Kousik (2/17) and Thangarasu Natarajan (2/51) also chipped in with useful wickets.
Railways had a batting collapse on the day despite century from opener Saurabh Wakaskar (120) and 52 from Shivakant Shukla.
Once Shukla was out on his overnight score in the first over of the final morning, cleaned by Kousik, there was no stopping Tamil Nadu bowlers, who got wickets at regular intervals.
Mrunal Devdhar (6), Vasaimudi Chlevuraj (6) and Arindam Ghosh (15) and Mahesh Rawat (2) were dismissed cheaply as Railways were 196 for five. From there on, things only went downhill.
Brief Scores: Tamil Nadu 121 and 452/8 decl.