He felt that Nuremberg should have been awarded a penalty in the 0-0 draw against Eintracht Frankfurt last weekend, but it was not given.
Despite this, Frantz has urged his teammates to focus on one game at a time as they look to stay clear of the relegation places.
"In the second half against Gladbach almost no decisions went for us," Frantz is quoted by Bild as saying.
"As well as this, almost every 50-50 decision went against us. We did not even get given a clear penalty for handball.
"We should not worry too much about the table at the moment, but treat each game as if it were our last."
Nuremberg are currently 13th in the Bundesliga.