India set Sri Lanka a daunting target of 372 before reducing the hosts to 84-4 on day four of the opening test in Galle on Tuesday, remaining firmly on course for victory.
Sri Lanka's top order faltered for the second time in the match against India's disciplined attack, ending the day 288 runs short of the target with six wickets in hand.
Sri Lanka captain Dhananjaya de Silva was batting on 31 at stumps with first-innings centurion Sonal Dinusha on 25.
With a first-innings lead of 178, India came out with clear intent in their second innings, looking to plunder runs rather than accumulating them as they sought to leave enough time to bowl Sri Lanka out again in the rain-affected test.
Although wickets fell regularly, Rishabh Pant smashed an entertaining 66, while Devdutt Padikkal made 44 and KL Rahul added 35 as India were bowled out for 193 just before tea.
India suffered an early setback when Asitha Fernando had opener Yashasvi Jaiswal caught behind for a three-ball duck.
Rahul successfully overturned an LBW decision but threw away his wicket when he charged down the track to spinner Prabath Jayasuriya and attempted to clear mid-on. Jayasuriya also removed India captain Shubman Gill, who followed his first-innings score of 16 with eight.
Padikkal was trapped lbw by Keshara Nuwantha. The left-hander reviewed the decision but was unable to overturn it.
EFFECTIVE KNOCK
Pant produced a typically cheeky but effective knock to extend India's lead. The left-hander struck eight fours and two sixes, scoring nearly at a run-a-ball.
After being struck on the helmet by a Lahiru Kumara bouncer, Pant pulled the next delivery for four before being caught behind off Kumara attempting his trademark falling-away pull shot.
Pant became the first Indian batter and fourth overall to hit 100 sixes in test cricket.
Sri Lanka were forced into a change after Dinesh Chandimal injured his neck and shoulder while trying to save a boundary. Chandimal was taken to hospital for precautionary scans, with Pasindu Sooriyabandara playing his maiden test as a concussion substitute.
Mohammed Siraj bounced out Nishan Madushka for six and spinner Manav Suthar trapped the debutant lbw first ball.
Sooriyabandara was initially given not out, but Suthar persuaded captain Gill to review the decision and the verdict was overturned.
Kamindu Mendis did not last long either, edging Prasidh Krishna to first slip as Sri Lanka's top order quickly unravelled.
De Silva, then on seven, got a huge reprieve when he edged Ravindra Jadeja to slip but the spinner had overstepped.
