The Mizo outfit,went ahead in the 27th minute after KC Lalchhuanmawia exploited poor defending, four minutes before Lalchhuanmawia crept up on Services goalkeeper M Nanao Singh who was caught unaware while bouncing the ball, leading to a brilliant goal by skipper Zico Zoremsanga from close range.
With its pride dented by two quick goals, Services, which won the tournament in 2012 and 2013,pushed to reduce the margin and against the run of play, striker Arjun Tudu pulled one back in the 43rd minute.
However, Mizoram struck to its attacking postures and the third goal by substitute V Laltanpuia in the 71st. minute was the one that removed all doubt, giving the north-eastern state a 3-1 lead in the game and a certain place in the last four.
The Mizo team, which trounced defending runners-up Kerala 3-1 at the same venue on the opening day on February 24, made sure of the third consecutive win in the final round with Lalbiakhlua's right-footed shot from outside the area three minutes before the final whistle.
The team is now at the top of the table with nine points from threematches.