The spin of the coin allowed Bhutan to go through to the semi-finals of the football tournament in the ninth SAF Games in Rawalpindi on Wednesday.
The points' table in the three-team Group BBB was such that Bhutan needed to beat Sri Lanka or lose by not more than a 0-1 margin in Wednesday's league match.
The Lankans won by a solitary goal, scored by skipper Siyaguna Kosgodage, to score their second victory and forced a tie between Nepal and Bhutan, who had earlier drawn their match for a point each.
Sri Lanka had beaten Bhutan 1-0 on Wednesday, the goal coming through Weerasinghe Siyaguna in 13th minute.
Since the points, goals for and against were the same (one point each and one goal each against), for Buthan and Nepal, the organising committee applied FIFA rules to resolve the issue.
A meeting with the team managers of Nepal and Bhutan was held before the coin was tossed in front of the cameras and public at the stadium.
Luck favoured Bhutan, and Nepal, a regular figure in the semi-finals of previous tournaments, were ousted.
In Group AAA, India have four points from two matches, following a goalless draw with Bangladesh on Sunday and a solitary goal victory over Pakistan, who have three points from a victory over Afghanistan.
Debrata Roy scored India's only goal against Pakistan, from a penalty in the 70th minute.
India plays Afghanistan in their third and final league tie, while Pakistan take on defending champions Bangladesh.
In another match on Tuesday, defending champions Bangladesh beat Afghanistan 2-1.
Bangladesh's striker Mehedi Hassan scored twice, in the third and 43rd minutes, while Rozeddin scored for Afghanistan in the 72nd minute.