Bowled out for a modest 233 in their first essay, Mumbai came out all guns blazing and skittled out Karnataka for a paltry 130 in their first innings on the dramatic second day of the Ranji Trophy final at the Gangotri Glades in Mysoore on Tuesday.
However, having conceded a 103-run lead, Karnataka's seamers hit back to have the Mumbaikars in a tizzy at 51 for five.
Abhishek Nayyar (batting 32) and Daval Kulkarni (batting 35) pulled the visitors out of woods, posting 57 runs for the unbroken sixth-wicket.
At draw of stumps, Mumbai were 108 for five, a lead of 211 runs, with five wickets remaining.
As many as 14 wickets fell in the absorbing contest between bat and ball today, with Avishkar Salvi, who claimed his season's best figures of 5 for 31, and Abhimanyu Mithun producing outstanding spells with the cherry.
Mithun's second innings burst (4 for 30) saw him share the honour of being the season's highest wicket-taker with R Vinay Kumar. Both have bagged 44 wickets each.
Vinay Kumar and Daval Kulkrani were never short of effort and strived to get wickets with every delivery.
Resuming at their overnight 15 for one, Karnataka lost wickets in a heap, as an accurate Salvi and Kulkarni (2 for 52) produced wicket to wicket spells.
Salvi used the moisture in the surface to repeatedly beat the flailing bats of the jittery, inexperienced Karnataka batsmen, who had dominated the season until today.
Only KB Pawan made a respectable 33 in 116 minutes. The youngster played some crunchy cover drives before being superbly gobbled up by Romesh Powar off Salvi at mid-off.
Batting a second time round, Mumbai lost Wasim Jaffer (8), Ajinkya Rahane (4), Omkar Khanvilkar (0) in a trice to an inspired Mithun with barely 18 runs on board.
Karnataka were back in the reckoning when Suhil Kukreja was caught at short-leg by Ganesh Satish off Vinay Kumar, and Vinayak Sawant fell to short ball from Mithun.
But Nayyar and Kulkarni put the brakes on Karnataka's resurgence.
With fortunes swinging like a pendulum, the title could be wrested by the team which shows more resolves and applies itself to the task on the morrow.
At the moment though, Mumbai are clearly ahead of Karnataka.
Mumbai (1st innings): 233 all out
Karnataka (1st innings): (overnight 15 for 1)
KB Pawan c Powar b Salvi 33
R Uthappa c Jaffer b Kulkarni 9
R Vinay Kumar c Nayyar b Agarkar 2
Ganesh Satish c Khanvilkar b Salvi 10
Manish Pandey lbw b Salvi 0
Amit Verma c Agarkar b Nayyar 8
CM Gautam c Jaffre b Kulkarni 16
Stuart Binny (run out) 13
Sunil Joshi c Sawant b Salvi 17
Abhimanyu Mithun lbw b Salvi 5
Sreenath Aravind (not out) 4
Extras: (LB-6, NB-7) 13
Total: (all out in 49.3 overs) 130
Fall of wickets: 1-10, 2-26, 3-53, 4-53, 5-58, 6-71, 7-95, 8-120, 9-120.
Bowling: Ajit Agarkar 12-4-30-1; Daval Kulkarni 19-2-52-2; Avishkar Salvi 13.3-6-31-5; Abhishek Nayyar 4-1-9-1; Romesh Powar 1-0-2-0.
Mumbai (2nd innings):
S Kukreja c Satish b Vinay 13
W Jaffer c Gautam b Mithun 8
A Rahane c Gautam b Mithun 4
OJ Khanvilkar lbw b Mithun 0
A Nayyar batting 32
V Sawant c satish b Mithun 10
D Kulkarni batting 35
Extras: (B-6) 6
Total: (for 5 wkts in 38 overs) 108
Fall of wickets: 1-10, 2-18, 3-18, 4-34, 5-51.
Bowling: R Vinay Kumar 13-3-43-1; Abhimanyu Mithun 13-2-39-4; Sreenath Aravind 8-3-20-0; Sunil Joshi 4-4-0-0.