Kulasekera gets a couple of boundaries off Nehra as Sri Lanka finish on 138-9 after being put into bat.
India won the toss and chose to bowl in their Asia Cup Twenty20 match against Sri Lanka on Tuesday.
India, who beat Bangladesh and Pakistan in their previous two matches, will qualify for the March 6 final with a win at the Sher-e-Bangla National Stadium in Dhaka.
Sri Lanka started the tournament with a 14-run win over minnows United Arab Emirates but were beaten by less fancied Bangladesh on Sunday.
They must win on Tuesday if they are to stay in the race.
Shikhar Dhawan returned for India after missing out on their five-wicket win over bitter rivals Pakistan due to injury.
Sri Lanka retained the same team that played against Bangladesh.
India:
MS Dhoni (capt), Shikhar Dhawan, Rohit Sharma, Virat Kohli, Suresh Raina, Yuvraj Singh, Hardik Pandya, Ravindra Jadeja, Ravichandran Ashwin, Jasprit Bumrah, Ashish Nehra.
Sri Lanka:
Angelo Mathews (capt), Shehan Jayasuriya, Tillakaratne Dilshan, Dinesh Chandimal, Thisara Perera, Milinda Siriwardana, Chamara Kapugedera, Dasun Shanaka, Nuwan Kulasekara, Rangana Herath, Dushmantha Chameera.
Umpires: Anisur Rahman (BAN) and Shozab Raza (PAK)
TV umpire: Sharfuddoula Ibne Shahid (BAN)
Match referee: Jeff Crowe
