Mumbai bowlers provided crucial breakthroughs at right times to tighten the noose around Delhi on the penultimate day of their Ranji Trophy Elite Group 'A' match at the Ferozeshah Kotla ground in New Delhi on Friday.
When play was stopped due to bad light on the third day, Delhi were 241 for six in their first innings, needing 160 more to avoid follow-on.
Resuming at 40 for no loss, Delhi made a sound start by putting up 72 runs for the first wicket.
However, Mumbai off-spinner Romesh Powar used his experience to rock the Delhi top order by removing the first four wickets, three of which fell for five runs.
Aakash Chopra, who scored 33 off 115 balls including five hits to the fence, was the first to fall as wicketkeeper Vinayak Samant stumped him off Powar in the 33rd over.
Powar then sent back Rajan Gupta (3) and opener Varun Kumar, who played 110 balls for his 19, in quick succession to leave Delhi tottering at 77 for 3.
Mithun Manhas and Rajat Bhatia built a brief partnership of 36 runs and things appeared to have settled down a bit for the hosts when Powar delivered his fourth blow by castling Bhatia (13).
Pradeep Chawla came in to join Manhas -- who remained unbeaten on 79 off 163 balls with nine fours -- for the rescue act and both of them played judiciously, by selecting the shots intelligently and rotating the strike.
They ignited a ray of hope for the Delhi camp by scoring 111 runs for the fifth wicket.
Mumbai skipper Nilesh Kulkarni rotated his bowlers to break the partnership, which was slowly bringing the hosts back to the match.
His trick to use Usman Maulvi's well directed bouncers clicked as Chawla hooked one straight to Vinit Indulkar at fine leg. Chawla made 48 off 126 balls, including four boundaries.
Kulkarni struck after a while as he trapped Abhinav Bali (14) before the wicket.
Mumbai coach Karsan Ghavri was pleased by his team's performance at the end of the day.
"Our bowlers bowled well. The fact that we were able to break the crucial Chawala and Manhas partnership would make the difference," he said.
He, however, did not make it clear if Mumbai could enforce a follow-on.
"It all depends upon how big lead we get tomorrow," Ghavri added.
Scorecard:
Mumbai (1st innings): 551 all out
Delhi (1st innings):
Aakash Chopra st Samant b Powar 33
Varun Kumar c Jaffer b Powar 19
R Gupta c Amol Mazumdar b Powar 3
M Manhas (batting) 79
R Bhatia b Powar 13
P Chawla c Indulkar b U Maulvi 46
A Bali lbw b Kulkarni 14
Sarandeep Singh (batting) 0
Extras (b-3, lb-6, w-6, nb-19) 34
Total (for 6 wkts in 98 overs) 241
FoW: 1-72, 2-76, 3-77, 4-113, 5-224, 6-241.
Bowling: Salvi 26-4-51-0, Usman Maulvi 24-6-54-1, Powar 24-10-65-4, Shetty 1-1-0-0, Kulkarni 16-5-28-1, Khanvilkar 5-0-16-0, Amol Mazumdar 1-0-2-0, Jaffer 1-0-15-0.