A total of 18 wickets fell in Vadodara as four wickets each from medium-pacers Sumit Narwal and Pradeep Sangwan saw Saurashtra fold for 92 before Delhi went to stumps on 194 for 8 with a 102-run lead.
Delhi, who need an outright win to be assured of a playoff spot, chose to field. Wicketkeeper Snell Patel (26) and Kishan Parmar (12) scored 24 runs for the first wicket, but the latter's dismissal saw Saurashtra quickly fall to 35 for 4. Narwal and Sangwan removed the top seven batsmen, before part-time offspinner Nitish Rana took two wickets with the score on 81 in the 30th over. Saurashtra folded for 92 inside 34 overs. Prerak Mankad top-scored for the third Saurashtra innings in a row with his 33.
Shikhar Dhawan and Gautam Gambhir opened Delhi's innings and were out in consecutive overs after scoring 16 runs each. Their wickets were part of a collapse that saw Delhi go from 38 for no loss to 57 for 4. Rishabh Pant then hit a 28-ball 40 to take Delhi past Saurashtra's score before Kushang Patel had him caught. Kushang finished the day with four wickets as he troubled Delhi's middle order who were 128 for 7 at one stage, before a 62-run stand for the eighth wicket between Manan Sharma (33) and Sangwan (39*) took them to stumps with a sizable lead.
Vinay Kumar took his third five-wicket haul this season as Karnataka dismissed Maharashtra for 163 before finishing the day on 67 for 1 in Mohali. The spell also saw him move past Madan Lal's tally of 351 wickets to become the leading wicket-taker among seamers in Ranji Trophy history.
Maharashtra, who also need an outright win to qualify, were put into bat. Openers Swapnil Gugale (25) and Rohit Motwani (32) added 42 runs for the first wicket before the former was caught behind off Stuart Binny. The next six overs saw only 3 runs, before Vinay picked up three middle-order wickets as Maharashtra lost six batsmen before they reached 100. Motwani, the innings' top scorer, was removed by Binny as the team's seventh dismissal on 113, which was followed by a brief resistance from the lower order before they were wrapped up for 163.
Although Karnataka lost debutant opener Arjun Hoysala in the first over to Anupam Sanklecha, his partner Ravikumar Samarth (33*) put on 67 with Kaunain Abbas (30*) to cut Karnataka's deficit to 96 runs.
Noida saw only 46 overs of play due to inclement conditions. Play only began after the scheduled lunch time, and Rajasthan were bowled out for 140 by Vidarbha.
Each of Vidarbha's five bowlers had wickets to their name, as Rajasthan's wickets fell within 98 runs after openers Amitkumar Gautam (18) and Manendar Singh (27) had put up 42 runs for the first wicket. This included collapses of 4 for 5 and 6 for 50 on either side of a 43-run fifth wicket stand between Rajat Bhatia (26) and Siddharth Dobal (19). Left-arm spinner Aditya Sarwate finished with 3 for 22 while Shrikant Wagh, Rajneesh Gurbani and Lalit Yadav took two wickets each.
In response, Vidarbha openers Sanjay Ramaswamy and Faiz Fazal played out the day's last four overs and took them to stumps on 14 for no loss.