Nagpur: Rest of India openers Abhinav Mukund (86) and Murali Vijay (77) struck unbeaten half-centuries to end day three at 172 for no loss and put their side in a commanding position in the Irani Trophy match here on Saturday.
As bad light ended the day's proceedings early, Rest of India took an overall lead of 210 with all their wickets in hand.
Mukund and Vijay batted together for 55 overs after Rest of India bowlers polished off Mumbai tailenders in quick time, needing just 6.5 overs to bowl the opposition out for 230 in the morning.
Resuming at 200 for six, Mumbai could add just 30 runs while losing four wickets to hand a 30-run first innings lead to Rest of India.
Munaf Patel added two more wickets to his three on Friday to complete his fiver for 70 runs, while S Sreesanth dismissed two more Mumbai batsmen to end at 3-46.
Mukund, sent in to open instead of skipper Virender Sehwag, and Vijay did not allow to go waste their bowlers' fine effort by playing sensibly and carrying their bats through the day.
Vijay was more aggressive of the two openers and his 146-ball 77 included 10 hits to the fence. Mukund had six fours in his 184-ball innings of 86.
It will now be a huge task for Mumbai to avoid a defeat as Rest of India have still all the wickets intact and two days remaining in the tie.
With the likes of the explosive Sehwag, S Badrinath, Ravindra Jadeja and Manoj Tiwary to come to bat, Rest of India would look to pile a huge lead before asking Mumbai to bat again.
Sreesanth removed overnight wicket-keeper batsman Vinayak Samant in the fourth ball of his first over and the day's second for 19, which also broke the 42-run stand for the seventh wicket with Ramesh Powar.
Next over, Patel bowled Powar who made a defiant 83-ball 27.
Dhawal Kulkarni made a last-ditch effort to erase his side's first innings deficit with some lusty blows but fell to Sreesanth for a 20-ball 23, which included five hits to the fence.
Iqbal Abdullah (5) was the last Mumbai batsman to fall, with Patel taking his wicket.
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