Germany international goalkeeper Rene Adler had a night to forget as he was involved in two howlers during Mainz's DFB Cup exit to Eintracht Frankfurt.
His wayward touch from a routine back-pass allowed Ante Rebic a simple opener with a quarter of an hour gone in the last eight of the cup.
But things went from bad to worse after half-time, when Alexander Hack turned Sebastien Haller's innocuous-looking cross beyond the keeper - who should have kept it out.
Omar Mascarell added a third for the hosts with an hour gone before Danny Latza's red card eight minutes from time put the icing on a miserable cake for Mainz, who have now lost their last three games without scoring.
Frankfurt will face one of Bayern Munich, Bayer Leverkusen or Schalke in the semi-finals.
Hit play on the video above to see Adler's howlers.