Haokip gave Bengaluru the lead in the 52nd minute before Australian defender Erik Paartulu made it 2-0 in the 69th minute.
The home team struck twice in the space of two minutes -- Anatoliy Vlasichev scoring in the 71st and Ibrahim Mahudee finding the target in the 73rd -- latching onto an error from Nishu Kumar at the National Stadium last night.
Haokip then scored his second of the night in the 78th minute to ensure that the 2016 runners-up take a slender advantage into the return leg in Bengaluru on February 20.
Roca also expressed unhappiness at the condition of the pitch.
"I feel we were lucky, because the last 20 minutes were awful for us, physically. The weather and pitch conditions were not something we would have liked and they (TC Sports Club) made most of it scoring twice and could have equalised late on," he said.
"It was tough for us during the game as well because they are a team that keeps pushing you. They are aggressive and have some good quality in their side. We were aware about it, but it was very tough in the last quarter as many of the players were not in a good condition."
Asked about his side letting in two quick goals, he said, "It was a tough game, but after 2-0 I thought we will be able to manage the game by keeping the ball, just how we wanted.
"We were not physically good and after the first goal, we panicked a bit, and in these moments, you generally have to work hard to do the normal things. They capitalized and scored immediately."
He said his side will have to be alert in the second leg match.
"I know it will be an advantage (scoring two away but at the same time, we must be alert in the second leg. TC Sports Club showed good character at 0-2 down to level the score. They will surely create problems for us if we are not aggressive enough at home."
After a goalless first half, the match burst into life after the half-time break, with Haokip's glancing header off a corner in the 51st minute giving Bengaluru the lead.
Another corner in the 69th minute saw Bengaluru widening their lead with Erik Paartalu nodding home.
Bengaluru looked to be cruising but TC Sports Club refused to wilt and pulled one back through Vlasichev Anatolii in the 71st minute, with his shot flying into the top right hand corner of the net.
That set the stage for an exciting finish as both teams went in search of a winning goal but it was to be Bengaluru's night as Haokip turned hero with a scorching effort, turning his marker before unleashing a shot from 20 yards out.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)