Bundesliga - Dortmund win to go 15 clear
Borussia Dortmund raced into a 15-point lead at the top of the Bundesliga with a hard-fought 1-0 victory over visitors Cologne that took them closer to their first German title since 2002.
Dortmund's 19th win in 25 games lifted them to 61 points before second-placed Bayer Leverkusen welcome VfL Wolfsburg on Saturday.
Champions Bayern Munich, whose title defence all but ended last week with defeat by Dortmund, are fourth on 42 points and travel to third-placed Hanover 96 on Saturday.
"This must be one of the most deserved 1-0 wins ever," said visibly relieved Dortmund coach Juergen Klopp. "My players worked non-stop over 90 minutes and we created many chances."
Cologne felt the full force of Dortmund's formidable attack early on but Rensing, who joined the club on a free transfer this season after leaving Bayern, was in superb form and kept the hosts at bay several times with spectacular saves.
Dortmund's pressure finally paid off when Lewandowski picked up the ball outside the box and scored with a powerful drive which went in off the post.
Cologne striker Milivoje Novakovic should have levelled after 56 minutes when he raced clear but shot wide from eight metres in their only real chance of the second half.