In many ways, this has been the World Cup of the underdog. Cape Verde and Curaçao have both made history at the tournament and there will be further underdog stories written before the final in New Jersey on July 19.With the World Cup moving into the final round of group stage fixtures, there could be even more scope for upsets as some of the stronger sides rotate their squads in preparation for the knockout rounds.Here are four matches to look out for before the group stage concludes.Ecuador-GermanyOne point from two games against Ivory Coast and Curaçao certainly isn’t the points haul Ecuador would have hoped for heading into their final group game against Germany, but there’s still reason to believe they can spring something of a surprise against the four-times World Cup winners.Ecuador’s defence remains their strongest asset. They conceded just five goals in 18 qualifiers and have looked solid at the back at the World Cup so far, only conceding a late goal to the Ivory Coast and keeping a clean sheet against Curaçao.It’s at the other end of the pitch where Ecuador have experienced issues. If, however, Enner Valencia can find his shooting boots or Germany allow a lapse in concentration, this could be a tactical match-up that suits the South Americans more than the two games they have underwhelmed in so far.Turkey-USANo matter what happens in Turkey’s final group game, their World Cup campaign has been a failure. Widely tipped to make it out of Group D, Vincenzo Montella’s side are already out of the competition following back-to-back defeats to Australia and Paraguay. Meanwhile, the USA have six points from a possible six so far.