The Billy Goats's hearts broken in injury time.
Dortmund started the game on the front foot and nearly opened the scoring as early as the sixth minute when Lucas Barrios headed over from just outside the six-yard box, following a cross by Jakub Blaszczykowski.
Three minutes later Lukas Podolski reminded everybody of his class when he hit the bar with a wonderful shot from outside the penalty area. This did not prove to be a sign of things to come from the visitors as Der BvB were tightening the grip and looked likely to score soon.
Ex-Bayern Munich defender Mats Hummels saw a header crash into the bar in the 16th minute with Miro Vardovic beaten, but a goal for Dortmund was just around the corner. Shinji Kagawa was at the center of things yet again as an inch-perfect cross from the Japanese four minutes later was converted collectively by Jakub Blaszczykowski and Lucas Barrios at the near post, but it was Kuba who took credit for the the goal.
After the first strike of the night the game became scrappy and continued to offer little in terms of excitement until the forty-minute mark. First Lucas Barrios wasted a carbon copy of the chance he missed early in the game and later Kevin Großkreutz failed to beat Miro Varvodic in a one-on-one situation. This proved to be the final moment of interest for the first period as the visitors went into half-time with a tender lead.
The Billy Goats stepped up their game after the break and could have clawed one back, had it not been for Adam Matuschyk who missed a free header from the center of the box twelve minutes after the second half whistle. Petit stung Roman Weidenfeller's hands with a wonderfully struck free-kick from outside the box in the 61st minute as FC Cologne were showing signs of improvement.
It took Koeln twenty minutes more to finally break down a resolute Dortmund defense and it was Lukas Podolski who crowned the hosts' efforts after half-time with a splendid finish in the top right corner from just outside the penalty area.
Lady luck smiled on Dortmund, however, as Nuri Sahin popped up with the winner in injury time to break the Billy Goats' hearts.
The win sees Der BvB top the Bundesliga, while Koeln stay in the relegation zone. Borussia host Hoffenheim in eight days, while FC Cologne visits Hannover 96 a day earlier.
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