Joshuel Pravin Vinson had been nominated as one of his battalion's best soldiers during his basic military training.
He was shortlisted for the Special Operations Force selection trial.
He was awarded the Battalion Best National Serviceman of the Year this year for his contributions to the 40th Singapore Armoured Regiment.
His commanders even wrote a letter requesting for him to leave Singapore to attend an exercise in Australia while a criminal charge was still pending.
But all of that may come to naught after Joshuel, 23, a lance corporal, was on Monday sentenced to six months' jail for being a member of an unlawful assembly whose objective was to hurt others.
The full-time national serviceman is the first of 18 people - a group that includes alleged Pak Leong Gang leader Mahaithiran Muthukumal, 34 - to be charged and sentenced.
It started as a fight between the Pak Leong Gang and a rival gang in an industrial estate and was followed by a car chase that led to the HDB flat of their alleged leader in Yishun in the early hours of June 8.
Joshuel's gang has territories in the Woodlands and MacPherson areas.
Before the incident, police investigations revealed a previous conflict between two members from Pak Leong Gang and KCOW Gang.
Joshuel met eight of the other accused persons from Pak Leong Gang, excluding Mahaithiran, at a coffee shop in Woodlands on the night of June 7.