Cologne sank even further into the Bundesliga relegation zone after they were stunned at home 2-0 by bottom club Darmstadt on Saturday.
Darmstadt found the breakthrough in the 57th minute after Cologne failed to deal with a corner. The ball fell to Christoph Klarer, who fired his shot between the legs of a defender and goalkeeper Marvi Schwäbe. Oscar Vilhelmsson scored in stoppage time to put the game to bed.
RB Leipzig scored a late goal in as 2-1 win against Heidenheim as they bid to qualify for the Champions League. Nikola Dovedan cancelled out Benjamin Sesko's opener in the 69th, but Leipzig claimed the win in the 85th thanks to Lois Openda.
Leipzig are fourth, currently the last spot for next season's Champions League, and three points ahead of fifth-placed Borussia Dortmund, who host newly-crowned champions Bayer Leverkusen on Sunday.
The Bundesliga, however, is closing in on a fifth Champions League spot, with ruling body UEFA awarding the top two nations in its events this term with an additional slot. Germany are currently second in the UEFA season rankings.
Wolfsburg, meanwhile, took a breather and increased their gap to the drop zone thanks to a 1-0 win against Bochum, another relegation candidate. Elsewhere, Hoffenheim claimed a 4-3 stoppage-time win in a thrilling home match against Borussia Mönchengladbach.