Werder Bremen took over second place and extended their unbeaten run to 19 games by sharing the spoils at home with Borussia Dortmund in a 1-1 draw.
Mesut Ozil gave Bremen the lead in the 36th minute only to see Lucas Barrios equalise nine minutes after the break.
Hamburg missed the chance to stay on the heels of leaders Bayer Leverkusen after being held to a 2-2 draw at Hannover. Marcell Jansen put the visitors ahead after 15 minutes before Didier Ya Konan equalised in the 28th minute.
Eljero Elia restored Hamburg's advantage just before half-time only for Jiri Stajner to convert a late penalty for the second equaliser of the afternoon.
Rock bottom Hertha Berlin suffered another defeat as Cologne pulled away from the foot of the table with a 1-0 win in the capital.
Milivoje Novakovic scored the only goal of the game 11 minutes from time.
