Koln will continue to play Bundesliga football next season after thrashing Holstein Kiel 5-1 in their relegation playoff second leg.
Having finished 16th, Koln faced a two-legged tie against the team who finished third in the second tier to decide who would be in the top-flight next season.
A 1-0 defeat at home in the reverse fixture earlier in the week had them staring at relegation but a first half blitz at the Holstein-Stadion meant they live to fight another day in Germany’s top division.
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Jonas Hector levelled the aggregate score after just three minutes for the visitors but Kiel hit back immediately through Lee Jae-sung.
A minute later, Sebastian Anderson restored Koln’s advantage on the day and then put them 3-1 up and in front in the tie for the first time on 13 minutes.
Rafael Czichos added a fourth five minutes before the break in a breathless first half.
Koln managed the game in the second half and Ellyes Skhiri wrapped up the scoring five minutes from time.
The result means Koln remain in the Bundesliga for a second successive season following their most recent promotion in 2019.
Keil, who were playing in the German fourth tier as recently as 2013, saw their remarkable rise up the divisions brought to a halt and will be aiming for promotion again next season.
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