Second-division Greuther Fuerth joined Bayern Munich, Borussia Moenchengladbach and Borussia Dortmund in the semi-finals of the German Cup after they shocked Bundesliga side Hoffenheim 1-0 on Wednesday.
Bayern are chasing their 16th German Cup title and are into Saturday's draw for the last four after their 2-0 quarter-final win at VfB Stuttgart with France wing Franck Ribery scoring the opening goal.
After Brazil defender Rafinha found some space on the right wing, Germany midfielder Thomas Mueller produced a defence-splitting pass which allowed Ribery to fire home from close range with half an hour gone.
Mario Gomez added the second a minute after the break when he followed up his own shot and netted the rebound to score against his old club.
Second division Duisburg reached last year's final and Fuerth are threatening to do the same after dispensing with Hoffenheim.
Canada striker Olivier Occean grabbed the all-important winner just a minute shy of the half-time break.
Having knocked Nuremberg out in the third round, Fuerth have now claimed German league scalps in consecutive rounds and one of the Bundesliga's top four teams awaits them in the semi-finals on March 20 and 21.
Gladbach needed added time to squeeze past Hertha Berlin on a bitter night in the capital city in temperatures of minus 12 at the Olympic Stadium.
Belgium defender Filip Daems netted a penalty in the 101st minute before Sweden defender Oscar Wendt scored the second in the 120th minute with his first touch of the game less than a minute coming off the bench.
On Tuesday, Borussia Dortmund coach Jurgen Klopp admitted he was far from happy the German league leaders had to play in arctic-like temperatures in their 4-0 German Cup quarter-final win at minnows Holstein Kiel.
"It was like ice hockey on grass," fumed Klopp as the live-screened match went ahead even though the pitch at Kiel's Holstein Stadion ground was partly frozen amidst temperatures of minus 18 celsius.
"There was a great danger the players were going to get hurt."
Klopp's concern was understandable with his side two-points clear at the top of the German league and they face Bayer Leverkusen on Saturday in the Bundesliga.
Poland striker Robert Lewandowski put Dortmund ahead after 11 minutes before Japan winger Shinji Kagawa doubled the lead seven minutes later when he fired home from the edge of the penalty area.
Just as he did in last Friday's 2-0 German league win at Nuremberg, Paraguay striker Lucas Barrios came off the bench and scored Dortmund's third in the 80th minute.
Croatia midfielder Ivan Perisic completed the scoring when he wrong-footed the defence with a quick free kick three minutes from time.