Nacional was on track for a hard-fought 1-0 away win against Independiente on Thursday (AEST), but Mina scored from a set-piece in the 87th minute in front of a capacity crowd at Estadio Olimpico Atahualpa in Quito.

The late drama, which came after Orlando Berrio put his team ahead, leaves the tie delicately poised ahead of the return leg in Medellin on 28 July.

Independiente started the game brightly and could have taken the lead inside the opening minutes but failed to force Nacional goalkeeper Franco Armani into an early save. 

Armani was then forced into action in the 21st minute when a dangerous free-kick was directed towards goal by defender Mina, but Nacional's shot-stopper managed to collect the threatening effort.

As the game wore on, it was Nacional which looked the more threatening of the two sides, and in the 36th minute its dominance was rewarded with a goal. 

Berrio collected a pass from Macnelly Torres and held off a challenge from Mina before gliding past two defenders and firing a shot from just outside the box, beating Librado Azcona with an effort into the bottom left-hand corner.

The strike was Berrio's fourth in the Libertadores this season, with the 25-year-old having scored twice in the group stages and one in the quarter-finals against Rosario Central. 

Nacional almost doubled its advantage a few minutes later when Marlos Moreno - who is reportedly Manchester City-bound after next week's second leg - hit a half-volley from distance, but the thunderous attempt dipped just over the crossbar. 

Independiente pushed for a vital equaliser in the second half but struggled to find a way past Armani, with the Argentine goalkeeper making a crucial save off a free-kick in the 63rd minute. 

However, Independiente's late push for an equaliser eventually paid off, with Mina slotting the ball home from close range after Junior Sornoza's free-kick.