Vasco Sports Club, Goa, warded off a late charge from Mahindra United to earn a goalless draw in an eighth National Football League match in Margao, Goa, on Friday.
The draw kept Mahindra in third position, with 37 points from 20 matches, two points behind Dempo, who are placed second.
East Bengal, with 46 points from 20 matches, have already clinched the title for third time having taking an unassailable lead.
Vasco, who are in seventh place, have 27 points from 20 matches, and are safe from relegation.
Mahindra started promisingly with defender Lawson initiating the moves from his own half on the flanks. They came close to scoring but Raphael Patron's first shot went out and later S Venkatesh's weak header went straight to keeper Rogeiro Ramos.
Vasco, who relied on counter moves in the first half, had a chance midway through the first half but Sushant Mathews's left-footer missed the target narrowly.
Vasco, who lacked the thrust in the upfront in the first half, brought in Amaechi Tochukwu in place of Levy Coelho and made inroads more often. They had two clear chances to score but Amaechi headed over from close off Marcos Pereira's cross and later Marcos himself shot wide following a pass from Kamal Thapa.
Vasco, who kept on the pressure, were unlucky when Vinu Jose's 40 yards shot hit the post after brushing the outstretched hand of 'keeper Kalyan Chaubey.
But Mahindra fought back in the last quarter of the match as they went for the kill. The woodwork came to Vasco's rescue when a long ranger from James Singh hit the bar.
Referee P Bhaskar showed yellow cards to Mahindra's Arun Malhotra and Vasco's Kamal Thapa and Denis Cabral.