Fourth-tier part-timers Roedinghausen made mighty Bayern Munich work for a 2-1 away win in the second round of the German Cup on Tuesday.

It was a poor performance from reigning Bundesliga champions Bayern, and the win came at a price as Thiago Alcantara had to be helped off with 15 minutes to go.

"We have got through but everyone needs to think about their performance here," said goalscorer Thomas Mueller.

"We played well for the first 20 minutes, but then we made a lot of mistakes and became nervous."

Bayern were 2-0 up after just 13 minutes in Osnabrueck when stand-in striker Sandro Wagner netted and Mueller converted a penalty in freezing conditions.

Bayern wasted the chance to increase their lead on 23 minutes when Renato Sanches fired his penalty attempt against the crossbar.

Despite trailing by two at the break, Roedinghausen dreamt of an upset after midfielder Linus Meyer drilled in on 50 minutes to cause nervous glances in the Bayern ranks.

Bayern coach Niko Kovac named a weakened team but still started with 11 internationals.

They took the lead after just eight minutes at Osnabrueck's Bremner Bruecke stadium, the 16,000-capacity ground which could have housed the entire population of the nearby municipality of Roedinghausen.

Wagner stabbed home a Sanches volley to give Bayern an early lead.

When Sanches was pulled down in the area, Mueller put away the penalty and the Bavarians appeared on course for a routine win.

It should have been 3-0 when Leon Goretzka was fouled in the area, but Sanches smashed his spot-kick off the crossbar.

Roedinghausen came out with renewed energy after half-time and midfielder Meyer soon had the delight of scoring past Germany goalkeeper Manuel Neuer.

With 15 minutes left, Roedinghausen goalkeeper Niclas Heimann pulled off a remarkable save to deny Franck Ribery but there was ultimately no fairytale for the hosts.

Elsewhere fourth-tier Ulm, who knocked out holders Eintracht Frankfurt in the first round, bowed out after being thumped 5-1 at home by Bundesliga strugglers Fortuna Duesseldorf.

Wolfsburg carved out a 2-0 win at Hanover 96 in an all-Bundesliga clash with their towering Dutch striker Wout Weghorst claiming his third goal in as many games.

Hertha Berlin also booked their place in the third round with a 2-0 win at third-division Darmstadt.

Hertha captain Vedad Ibisevic scored just seconds after coming off the bench before defender Maximilian Mittelstaedt added a late second.