Rupinder Pal Singh (36th minute) and Chinglensana (51st) struck for India while Pakistan's lone goal came from the stick of Mohd Waqas (57th) at Al Rayyan Stadium on Monday night.
The victory over Pakistan was India's fourth on the trot in the six-team tournament after they had comprehensively beaten China (4-0), Japan (3-1) and Oman (11-0) respectively in their earlier round robin league matches.
India play Malaysia in their last league match tomorrow. They are on top of league table with 12 points while Pakistan and Malaysia are both on seven points after four matches each.
After a barren first half, the game came alive soon after the interval. Youngster Danish Mujtafa sprinted past a host of defenders and entered the circle but was stick-checked by Pakistan defender in front of the goal, leading to Malaysian umpire Lingam Karuppusaky signal the only penalty stroke of the match just a minute into the second session.
Rupinder Pal Singh converted it for the first goal of the hotly-fought match (1-0).
Youngster Chinglensana made use of a gem of a pass from Gurwinder Chandi to enhance the lead through a field effort in the 51st minute (2-0).
Pakistan replied through their third penalty corner. Indian goalie stopped the shot, but Mohd. Waqas collected the rebound which was shoulder high and tapped in (1-2). The Indians protested for high ball, but the umpires stood their ground.
Shortly after Pakistan reduced the margin, India suffered on account of a yellow card to vice-captain Raghunath but managed to hold on to the lead till the end.