Hertha Berlin's lead at the top of the Bundesliga was slashed to one point after they slipped to a 2-0 defeat at VfB Stuttgart on Saturday, while Bayern Munich and VfL Wolfsburg both won.
Franck Ribery, left, helped secure the only goal for Bayern Munich against Karlsruhe
Champions Bayern overcame bottom side SC Karlsruhe 1-0 thanks to a goal from Argentine Jose Ernesto Sosa, while Wolfsburg made it seven league wins in a row with a 3-0 victory over Arminia Bielefeld.
Hertha have 49 points, with Bayern and Wolfsburg joint second on 48 with the same goal difference and goals scored.
The current rankings should make an intriguing meeting between the two sides in Wolfsburg in two weeks' time following next weekend's break for World Cup qualifiers.
Stuttgart responded from a 4-0 thrashing at Werder Bremen last week by hitting leaders Hertha Berlin with two quick goals after the break.
Cacau finished a minute after the interval, after a long free-kick downfield by keeper Jens Lehmann was headed on by Mario Gomez. Sami Khedira made it two five minutes later when he headed in Thomas Hitzlsperger's free-kick.
The best performance of the season
Khedira headed home a free kick cross from Thomas Hitzlsperger
"It was the best performance of the season since I have been in charge," said Stuttgart coach Markus Babbel, who took over in November after the dismissal of Armin Veh.
"For 60 minutes we played some really classy football, we created a lot of chances and were very concentrated -- a very accomplished performance."
The win keeps sixth-placed Stuttgart still well placed to mount a late challenge for one of the Champions League places.
Lehmann said: "Hertha are seven points away with nine games to go and a lot can happen, but I have got out of the habit of making forecasts."
Bayern closes the gap
Bayern meanwhile left the field to jeers after a lackluster victory over Karlsruhe who remain three points adrift of Energie Cottbus at the bottom.
Bayern Munich needed a single goal by Jose Sosa, left, to remain in the title hunt
Sosa, making a rare appearance in the Bayern midfield, scored his first goal for the club when he took a pass from Franck Ribery -- back in the side after injury -- to slot the ball past Markus Miller in goal in the 34th minute.
Bayern were anything but impressive after the break and almost conceded a goal in stoppage time when Ze Roberto cleared a Sebastian Langkamp header off the line after keeper Michael Rensing misjudged a corner.
Brazilian striker Grafite bagged his 18th goal in 16 league games as visiting Wolfsburg downed Arminia Bielefeld 3-0, with Christian Gentner and Ashkan Dejagah also on target.
Grafite's goal in the 59th minute drew him level with Hoffenheim's injured Vedad Ibisevic as the league's top scorer.
The Brazilian had set up Gentner's opener for Wolfsburg in the 19th minute, while Dejagah netted with a deflected shot three minutes from time.
Hoffenheim losing ground
Cologne's Milivoje Novakovic, left, scored the 2-0 with a penalty against Energie Cottbus
Fifth-placed Hoffenheim lost further ground when they were held 2-2 by visiting Hanover, leaving Ralf Rangnick's side without a win in seven matches.
Selim Teber gave Hoffenheim the lead from the penalty spot in the 20th minute but Hanno Balitsch responded two minutes later and Mario Eggimann headed Hanover in front in the 74th-minute before substitute Wellington leveled with six minutes remaining.
An Alex Frei penalty midway through the second half was enough to secure Borussia Dortmund a 1-0 win -- their first league victory of the year -- over visiting Werder Bremen, while Bayer Leverkusen were held 1-1 by Eintracht Frankfurt.
Cottbus remain deep in relegation danger after slipping to a 2-0 home defeat by Cologne. Slovenian striker Milivoje Novakovic mopped up from close range after an error from keeper Gerhard Tremmel in the 51st minute and then converted a penalty five minutes later.
Fourth-placed SV Hamburg could draw level on points with Bayern and Munich with a win at Schalke 04 on Sunday.
On Friday, visiting Bochum edged Borussia Moenchengladbach 1-0 in a relegation tussle.