Neuer has regained the gloves since returning to full fitness, though, and Ter Stegen accepts he is in a frustrating situation.
It is not easy to find an explanation as I am giving the best account of myself in each game to make the decision more difficult, Ter Stegen said.
I am trying [to become first-choice] anyway. But this trip with the national team has been a tough blow for me.
Ter Stegen, 27, has played 22 times for his country, who are on track to qualify for Euro 2020 after joining Northern Ireland on 12 points after five games.