Michael Ballack-inspired Bayer Leverkusen to beat Schalke 2-0 on Sunday to cut Borussia Dortmund's lead at the top of the Bundesliga table to just seven points.
Dortmund were held to a draw at home by Mainz on Saturday, tightening things at the top of the table with seven matches to go, but Borussia remain on course for their first German title since 2002.
First-half goals by Schalke's German defender Christoph Metzelder, who headed into his own net after 27 minutes, and Leverkusen's Eren Derdiyok sealed the win which keeps Bayer second.
Ex-Germany captain Ballack, 34, making only his tenth league appearance of the season after back-to-back injuries, was left out of the squad named on Friday to face Kazakhstan and Australia, but bolstered Leverkusen's attack.
He played the full 90 minutes and was heavily involved in the build-up for Deriyok's after linking with Germany team-mate Simon Rolfes and is showing glimpses of the form which saw him win 98 caps for his country.
The defeat leaves Schalke, who drew Inter Milan in the quarter-finals of the Champions League on Friday, tenth in the league and only a good performance by Royal Blues' Germany goalkeeper Manuel Neuer kept the score down.
On Saturday, Mainz poached a point at Dortmund as Croatia striker Petar Sliskovic's controversial late goal sealed a 1-1 draw.
Dortmund took the lead when Germany defender Mats Hummels managed to scramble the ball over the line after just eight minutes.
Turkey midfielder Nuri Sahin had a penalty saved after 19 minutes which proved costly in the dying stages.
With Dortmund defender Neven Subotic laid out on the pitch after taking a ball in the most delicate of areas between the legs, Mainz's Sliskovic fired home with time almost up.
Earlier, France star Franck Ribery netted a late winner to give Bayern Munich a 2-1 win at Freiburg as the Bavarian giants began their recovery after their Champions League exit.
Bayern are licking their wounds after they were dumped from the Champions League on Tuesday following a 3-2 defeat by Inter Milan in Munich.
The defeat means Bayern face a season without silverware as they remain fourth in the league, 14 points behind Dortmund.
Only a second-place finish in the Bundesliga will guarantee Bayern a Champions League place for next season.
Hannover took a step closer to European football next season with a convincing 2-0 win over Hoffenheim that leaves them third in the league and on course to qualify for the Champions League.
Hamburg, whose coach Armin Veh was sacked last Sunday after their 6-0 defeat at Bayern last weekend, bounced back with a 6-2 win at home to Cologne.
Werder Bremen look set to avoid relegation after their 3-1 win at Nuremberg kept them four points away from the relegation zone.
Eintracht Frankfurt stayed above the bottom three after a 2-1 win over St Pauli, who remain in the drop zone.
On Friday, Borussia Moenchengladbach were sent closer to their third relegation from the Bundesliga when they were beaten 1-0 by Kaiserslautern thanks to an own-goal by goalkeeper Logan Bailly.
Second-from-bottom Wolfsburg host Stuttgart on Sunday night with ex-Schalke coach Felix Magath, who guided Wolves to their 2009 German league title, back at the helm after his appointment on Friday.