Even though unusual, Colombia coach Nestor Lorenzo gambled to stay on the attack against Uruguay despite going down to 10 men, and it paid off as they emerged with a 1-0 win that set up a Copa America final against Argentina.

Colombia took a 1-0 lead before having right back Daniel Munoz sent off in first-half stoppage time of their semifinal in Charlotte, North Carolina on Wednesday.

Down a man for the whole of the second half, Lorenzo opted to keep two forwards on the pitch to create chances instead of sitting back and 'parking the bus'.

"One of the main topics we discuss is that we never want to be one man down. It is almost impossible to maintain performance with 10 players on the pitch," Lorenzo told reporters.

"Teams that were dominating their opponents when they were one man down were eliminated from the tournament. We really analysed that situation.

"With the formation, we only had two options of 5-4, 5-3-1 or to keep it 4-3-2 and create opportunities. We chose that one and God favoured us. Some of their opportunities didn't go in, but we also missed some goals and we made it."

Colombia could have doubled their lead at the end when Mateus Uribe missed two chances, but Lorenzo was just relieved to get the better of Uruguay coach Marcelo Bielsa.

"I think that to beat Bielsa, you need to walk many miles. He is a referent coach and I really admire him as a person. It was our turn to win, that's all," he added.

Lorenzo also refused to criticise Munoz, who picked up a second yellow card after elbowing Uruguay's Manuel Ugarte.

"Daniel is feeling a bit sad because he's a lion on the pitch and once more he got a bit emotional," he said.

Colombia's victory also set a national record of 28 matches unbeaten and Lorenzo paid tribute to former boss Francisco 'Pacho' Maturana, who went 27 games without defeat.