Adam Nawałka's were punished for failing to convert their numerous scoring chances and bowed to the Africans who were without captain John Obi-Mikel.
Victor Moses’ 61st-minute penalty worked the magic as the three-time African champions extended their unbeaten run to six.
Notwithstanding their victories over Argentina and the Polish side [teams placed fourth and sixth respectively on Fifa ranking], the German tactician has charged his ‘young team’ to stay humble and continue the momentum ahead of the global showpiece.
“We were lucky to have won this game against a very solid Polish side,” Rohr after the game.
“They created some big opportunities to score and were dangerous from set pieces that we found difficult to cope with but I praise my team for their victory.
“This team is a young team but also a team of leaders. If we stay humble and continue to work hard to improve our play we have huge potentials, but beating 2 FIFA top 10 teams in friendlies doesn’t mean we are now World Cup favourites.”
Nigeria will continue their preparation with another friendly match against Serbia on Tuesday at the Hive Stadium, London.