Last year's runners-up Services held on to a Laldingliana penalty to beat fancied Maharashtra 1-0 in a Group B quarter-final league match of the 63rd National Football Championship, for the Santosh Trophy, at the Jawaharlal Nehru stadium, in Chennai on Wednesday.
In another match later, fancied Goa were held goalless by Karnataka.
Maharashtra defender Anas Mohammed Kutty's attempt to block Services captain Shaji D'Silva inside the box resulted in the penalty and Laldingliana calmly slotted the ball into the net in the 11th minute.
Services then hung on gamely for the rest of the match to steal three points.
Maharashtra, boasting the likes of India midfielder Steven Dias, Paresh Shivalkar and Kuttimani Sampath Kumar, failed to work as a unit, making things easier for Services, who defended resolutely and showed excellent work ethics.
However, the 2006 runners-up did get some chances of their own but Services goalkeeper Robikanta Singh did well to stop two powerful efforts from Maharashtra skipper Dias.