The 19-year-old Sancho became the youngest to ever clock 15 goals in the league when he cancelled out Dominick Drexler's 29th-minute opener for Cologne in the 70th, then set up Paco Alcacer to seal the win in injury time after Achraf Hakimi gave Dortmund the lead in the 88th.
"The key was that we stayed calm," Dortmund captain Marco Reus said. "The game also showed that we're a long way off our potential." The visitors struggled until Lucien Favre introduced Hakimi and midfielder Julian Brandt in a double substitution in the 62nd. The latter was involved straight away and was decisive for the third goal with a brilliant ball forward for Sancho on a break.
Cologne was celebrating its first home game back in the Bundesliga following its promotion as second-division champion, but, despite a plucky performance, slumped to two defeats from two games following its 2-1 loss at Wolfsburg last weekend. The team was still applauded and cheered by fans long after the final whistle.
The fans also feted a new mascot, a goat named Hennes IX, who was attending his first game following the retirement of his predecessor Hennes VIII. The new Hennes, of a traditional but endangered domestic animal breed, took over this month as the older goat was forced to abdicate due to health reasons. Hennes VIII, the club's mascot for 11 years, was to remain available for visits at the local zoo.
Defending champion Bayern Munich, held by Hertha Berlin in the opening game, was to play at Schalke on Saturday.
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