Botafogo played almost the entire match with ten men after Gregore was sent off in the first minute but they showed impressive spirit and resilience to secure victory at River Plate's Monumental Stadium in Buenos Aires.

Midfielder Gregore was shown a red card after a wild, high challenge on Fauto Vera, forcing Botafogo to adjust their game plan, but Atletico failed to press home their numerical advantage.

Veteran forward Hulk had an effort from outside the box saved by John but the team from Belo Horizonte created little pressure.

Sensing the game might not be the rearguard action they might have expected, Botafogo began to show more attacking intent and they were rewarded in the 35th minute.

Marlon Freitas's shot from the edge of the box ricocheted around a crowded box before the ball fell to Luiz Henrique, who fired home from close range.

To their credit, Botafogo didn't retreat to defend their slim advantage and they were able to double their lead in the 44th minute.

Atletico defender Guilherme Arana attempted to shepherd the ball back to goalkeeper Everson but Luiz Henrique snuck between the pair and went down under challenge from the keeper.

After a VAR review, a penalty was awarded and Alex Telles confidently smashed home the spot kick to give Botafogo an unlikely 2-0 lead at the break.

Atletico, who won the Libertadores in 2013, made a triple substitution at the interval and it paid off swiftly with Eduardo Vargas heading in from a corner.

Inevitably, there was late pressure from Atletico, but Botafogo made sure of the victory when Junior Santos finished off a counter-attack deep in stoppage time.

With the win, Botafogo earns the final of 32 places in next year's FIFA Club World Cup to be held in the United States.