Mario Kempes weighed in on Argentina’s underwhelming performances Thursday, saying the team needed to show more courage like their compatriot Juan Martin Del Potro at the US Open.

“Two or three with the heart of Delpo [Del Potro] in the team and we wouldn’t have many problems or be criticized,” said the footballer-turned-commentator, a World Cup winner with Argentina in 1978. Jorge Sampaoli’s slipshod underachievers have taken a hammering from the Argentine media after a string of poor results – the latest a 1-1 draw with lowly Venezuela – left them in danger of not qualifying for next year’s World Cup tournament.

Unlike the footballers, Del Potro is the pride of Argentina after overcoming fever and a two-set deficit to beat Austria’s Dominic Thiem and set up a quarter-final victory over Roger Federer at the US Open this week. Del Potro, the world No 28, faces Rafael Nadal in Friday’s semi-final.Del Potro, the world No. 28, faces Rafael Nadal in Friday’s semi-final.