Vinicius, the 17 year-old forward who has already been signed by Madrid, came off the bench to see Flamengo overcome Emelec 2-1 in Group 4.
The Brazilian came on with his team 1-0 down in Guayaquil, where Brayan Angulo had put the hosts ahead with a deflected strike in the 65th minute.
But Vinicius took over from there, beating three markers down the right before cutting inside and finishing to make it 1-1.
He scored the winner in the 85th minute, playing a one-two with former Wolfsburg and Werder Bremen star Diego before curling a finish into the corner from just inside the area.
The result saw Flamengo move onto four points in Group 4, while Emelec remained winless.
In Medellin, 2016 champion Atletico Nacional thrashed a 10-man Delfin 4-0.
Dayro Moreno struck from the penalty spot before the visitor's task was made even harder as Luis Luna was sent off five minutes prior to half-time.
Atletico made the most of its numerical advantage early in the second half as Reinaldo Lenis scored twice and Macnelly Torres also netted.
The Colombian giant tops Group 2 on six points ahead of Bolivar, which drew 1-1 at home to Colo-Colo.
Elsewhere, Mariano Pavone came off the bench to score twice as Estudiantes cruised past Real Garcilaso 3-0, while Corinthians beat Deportivo Lara 2-0.