One week before a huge Copa Libertadores last 16 clash with Cruzeiro, Marcelo Gallardo has plenty to ponder after his River Plate side only just edged past Nacional B side Gimnasia y Esgrima de Mendoza.

Despite it being River’s first competitive game back from preseason it wasn’t supposed to be quite so difficult and if it weren’t for a couple of big moments from goalkeeper Germán Lux, the Millonarios could well have been on the end of another of the Copa Argentina’s big upsets.

Instead a perfect performance from the penalty spot sealed a place in the last 16 and a meeting with Godoy Cruz.

An early warning that it wasn’t going to be easy for River came with barely four minutes on the clock when Leonardo Ponzio was pickpocketed on the edge of the box and Lucas Carrizo one-on-one with Lux was his effort blocked.

River struggled to breakdown Gimnasia and aside from Julián Álvarez seeing a volley headed off the goalline there were little signs of an opener.

That was until the 56th minute when Fabricio Angileri bundled over Santiago López Garcia and gifted Gimnasia the opportunity to take the lead. Up stepped Ignacio Morales but once again Lux denied the Blanquinegro, the keeper’s legs deflecting the ball onto the crossbar and away.

Such wastefulness was swiftly punished by River as Exequiel Palacios nodded Benjamín Rollheiser’s scuffed volley past the wrong footed Tomás Marchiori and with the Libertadores champions ahead at last it looked as though the tie was over.

However, the lead lasted only four minutes with Renzo Vera heading in unmarked at a corner and with neither side able to find a winner the tie was forced straight to penalties.

River kept their cool and with each spotkick finding the target it eventually came down to Brian Andrada rattling the crossbar for Gimnasia and Rollheiser cooly scoring River’s fifth and final effort.

Los Millonarios move on to the last 16 but know that huge improvements are needed ahead of next week if progression in the Libertadores is to be secured.