An Arjen Robben goal in the 69th minute was enough to decide the Bavarian derby in favour of Bayern Munich against Nurnberg and take them to within three points of Borussia Dortmund at the top of the Bundesliga.
The Dutchman punished the hosts midway through the second half to give Jupp Heynckes's side the win they were looking for to increase the pressure on Dortmund at the top.
Nurnberg's fourth defeat in a row means they slip to within three points of the relegation zone with six games of the season remaining.
Nurnberg looked at least a match with Bayern early on and they had the first chance of the game in the seventh minute with Philipp Wohlscheid's header.
Bayern seemed a little tired after their midweek Champions League trip to Marseille and they were unable to show how they scored 20 goals in three games recently.
But one goal is still enough to win a game and they found that goal in the 69th minute.
Toni Kroos pounced on a poor pass from Maroh and he picked out Franck Ribery, whose powerful shot was saved by Raphael Schafer, but Robben dived in to convert the rebound.
Bayern had already found the back of the net three minutes earlier only for a tight offside decision against Thomas Muller to deny Mario Gomez.
Gomez also hit the woodwork late on with a header as Bayern tried to wrap up the win.
After a confident first half, Nurnberg seemed to lose their way a little in the second half and their response to falling behind came too late.
They nearly did grab an equaliser, though, when Almog Cohen's shot was pushed onto the crossbar by Manuel Neuer before Wollscheid missed with another header.
But Bayern held on to a deserved win which throws the Bundesliga title race open with a trip to Dortmund still on the agenda on April 11, and that game is looking increasingly like it will be a title decider.
