THE COPA LIBERTADORES has reached the last four stage and there’s some real continental heavyweights in there: Boca Junior, River Plate, Flamengo and Grêmio. The semi-finals include two domestic clashes which will guarantee an Argentina v Brazil final, the 15thtime the region’s two biggest football nations have met to decide the destination of the trophy. The all-Brazil semi-final is between Flamengo and 2017 winners Grêmio. Flamengo, the league leaders in Brazil beat fellow Brazilians, Internacional in the quarter-final. They’re in good form at the moment and consolidated their position at the top of Série A with a 3-0 win over Palmeiras on September 1. Flamengo and Palmeiras are two of the richest and culturally important clubs in Série A, with considerable financial clout on…