It’s not a situation Argentina are familiar with and for all their vehement denials of reports of rift between the players and the coach, they refuse to go away.So, even after midfielders Javier Mascherano and Lucas Biglia addressed a press conference on Sunday saying all is well, it did little to stop the rumours from swirling around the team before Tuesday’s must-win tie against Super Eagles Nigeria at the Krestovsky Stadium in Saint Petersburg. According to a number of reports, in the aftermath of a fall-out with coach Jorge Sampaoli, Sergio Aguero is set to be dropped. Aguero had reacted to Sampaoli’s comment that the players had failed to adapt to his style following the 0-3 loss to Croatia by telling a television channel: “Let him say what he wants.” ALSO READ: FIFA World Cup 2018: France out to show they’re special against DenmarkRegardless of his relationship with the players, Sampaoli will be expected to ring in changes. With the Argentina midfield being overrun in the 0-3 loss to Croatia, it looks unlikely that Enzo Perez would start again. But Mascherano is one of Sampaoli’s more trusted players and is expected to keep his place despite performances that have highlighted his age more than anything else.That said, it would be interesting to see how Sampaoli ---- so sure in his decisions four years ago while helming Chile and successfully plotting the exit of world champions Spain ---- deals with the midfield conundrum. Ever Banega has yet to start a game in this campaign but with Argentina struggling at the centre of the park, he would be expected to feature against Nigeria.So could Angel di Maria, who has often been a creative force for the national team playing in a midfield-three but had disappeared against Iceland and was dropped against Croatia. Paulo Dybala and Cristian Pavon too will be in contention to start.ALSO READ: FIFA World Cup 2018: Win or bust for Iceland against familiar foe CroatiaIn contrast to Argentina, Nigeria are on a high after the 2-0 win against Iceland in their last game with Ahmed Musa scoring a brace. Having started off with a 0-2 loss to Croatia, Gernot Rohr’s side looked more creative going forward against Iceland and will be confident of their chances against opponents who seem to be somewhere between disjointed and disintegrating.But Nigeria know that a draw may not be enough to take them to the knockout rounds should Iceland beat Croatia in the group’s other game that will be played simultaneously.Rohr changed his formation after Nigeria’s loss to Croatia. John Obi Mikel, who was played out of position as a No. 10, a move that drew criticism from his former manager at Chelsea Jose Mourinho, was given a deeper role against Iceland.ALSO READ: FIFA World Cup 2018: Soft centre stays a worry for GermanyThat helped Nigeria take control of the midfield and against an Argentina side that has struggled in that area so far, Mikel could well stamp his influence on the game.With a midfield-heavy 3-5-2 formation, Nigeria will fancy their chances against Sampaoli’s team. When the two teams faced each other in a friendly last November, Nigeria won 4-2.The circumstances are different ahead of Tuesday’s game but Nigeria will know this could be their best chance of ending their four-game losing streak to Argentina at the World Cup.