(CNN) -- Werder Bremen and Hamburg lost ground on German Bundesliga leaders Bayer Leverkusen after both dropped points on Sunday.
Leverkusen went four points clear with a 4-0 demolition of Eintracht Frankfurt on Friday, and that was reduced to three after second-placed Bremen were held 1-1 at home by Borussia Dortmund and Hamburg -- third on goal difference -- conceded a late equalizer in a 2-2 draw at Hannover.
Bremen, who extended their unbeaten run to 19 matches, took the lead in the 36th minute when midfielder Mesut Oezil gave Bremen the lead in the 36th minute with a left-foot effort from 12 yards following Aaron Hunt's cross.
It could have been 2-0 soon after but Mohamed Zidan cleared off the line as Per Mertesacker diverted Hugo Almeida's shot goalwards, then Dortmund's Lucas Barrios had an effort ruled out eight minutes after halftime.
But the Argentinian leveled a minute later with his fifth goal in the last five Bundesliga games when goalkeeper Tim Wiese could not hold Nelson Valdez's shot.
Hamburg led mid-table Hamburg after 15 minutes after Marcell Jansen stole possession and combined well with Eljero Elia before netting, but Didier Ya Konan equalized on 28 with a header from Constant Djakpa's corner.
Elia restored Hamburg's advantage just before half-time with a header from Piotr Trochowski's long free-kick, then the visitors hit the post through Tunay Torun.
Veteran Czech Jiri Stajner earned a point for improving Hannover with a late penalty after being brought down by Tomas Rincon two minutes from time.
His team moved up to ninth place after a run of three wins and a draw from the last five matches.
In Sunday's other game, Cologne moved away from the relegation zone with a 1-0 win at bottom club Hertha Berlin as Milivoje Novakovic scored the only goal 11 minutes from time.