Nigeria 'have to do it the hard way' to qualify from Group D, according to Garba Lawal.
An own goal from Oghenekaro Etebo and Luka Modric's penalty condemned Gernot Rohr's men to 2-0 defeat in their World Cup opener against Croatia on Saturday.
Although disappointed by the country's poor performance at the Kaliningrad Stadium, Lawal who represented Nigeria at the 1998 and 2002 World Cup tournaments has charged them to go all out for maximum points in their subsequent matches against Heimir Hallgrimsson's side and La Albiceleste.
"The way forward is we have to do it the hard way, now we have to win two matches which is very difficult," Lawal told Goal.
"I thought we were good but yesterday's performance showed the kind of quality we have. Iwobi and Moses played out of position, including Mikel. Everything we did yesterday didn't work well."
With the introductions of Ahmed Musa, Kelechi Iheanacho and Simeon Nwankwo failing to inspire the Super Eagles to a fightback, the former Elfsborg winger questions the depth of the squad.
"This is where a good bench comes
"Look at Russia, a team that knows what they are doing. The mission is to conquer Saudi Arabia, the substitutions they made in the game made them win. But, yesterday, I don't even know the formation the Super Eagles were playing."