Bundesliga: Five things we learned from last weeks round of matches

Bayern have gone from trailing Peter Bosz's Borussia by five points to holding a three-point lead over Dortmund, who they face away on Saturday.

Bayern Munich top the Bundesliga for the first time this season after beating ten-man RB Leipzig while Borussia Dortmund slumped again in their morale-sapping thumping at Hanover.

Since Jupp Heynckes replaced Carlo Ancelotti, Bayern have earned three straight league wins.

Bayern have gone from trailing Peter Bosz's Borussia by five points to holding a three-point lead over Dortmund, who they face away on Saturday.

Bayern wrestled control of the Bundesliga with a 2-0 win at home over third-placed Leipzig as Dortmund crashed again.

Their 4-2 thumping at Hanover saw them again caught on the counter-attack.

Their shaky defence was already responsible for a 3-2 defeat at home to Leipzig a fortnight ago and last weekend's 2-2 draw at Eintracht Frankfurt.

Here are five things we learned from the tenth round of German Bundesliga matches:

Heynckes' impact

Since Heynckes took charge on October 9, Bayern have taken maximum league points, scoring eight goals and conceding none.

Germany centre-backs Mats Hummels and Jerome Boateng are Heynckes' first-choice pairing which has tightened Bayern's defence significantly.

Against Leipzig, striker James Rodriguez scored the opening goal before Robert Lewandowski hit his 28th goal in 27th Bundesliga games in 2017.

James, on loan from Real Madrid, struggled under Ancelotti.

Heynckes has taken James under his wing, speaking to the Colombian in Spanish and when Kingsley Coman dropped out with injury, James took his place on the left wing with an impressive display.

Red mist Leipzig

In three of their last four games against Bayern, Leipzig have finished with ten men.

Captain Willi Orban was sent off just 13 minutes for bringing down Arjen Robben just outside the area on Saturday.

On Wednesday, Naby Keita was dismissed for a second yellow card when Bayern won the German Cup, second round clash on penalties.

Last December, Emil Forsberg was shown a red card after half an hour for scything down Philipp Lahm when Bayern thumped Leipzig 3-0 in the league.

Leipzig's tactic for the next meeting in March is simple.

"The motto is - to play with 11 against 11 until the end," quipped midfielder Marcel Sabitzer.

Dortmund struggle on

With one point in three league games, Dortmund's slump is now a mini-crisis after surrendering top spot to Bayern.

"I am speechless," said Dortmund's director Michael Zorc after Togo striker Ihlas Bebou netted twice as Hanover counter-attacked at will.

"That was sluggish and complacent - you won't win league match like that."

Centre-back Dan-Axel Zagadou, 18, was sent off in the second half, but Dortmund's defence had already been badly exposed.

The 4-1-4-1 formation leaves holes and has been criticised in the media.

"The problem wasn't the system. There wasn't - and there isn't - a crisis," insisted head coach Peter Bosz, even though results suggest otherwise.

"Hanover were more aggressive in the duals than us, we were too weak."

Red-faced Nagelsmann

Julian Nagelsmann was left red-faced when a bottle he hurled angrily, after Hoffenheim conceded a goal, struck a fan on the head.

Nagelsmann's Hoffenheim leaked three second-half goals without reply in the 3-1 home defeat against Borussia Moenchengladbach.

When Gladbach's Thorgan Hazard equalised on 61 minutes, Hoffenheim's head coach hurled the near-full bottle he was drinking from - which smacked a fan in the face.

"That was stupid of me, I actually meant to throw it against the wall, but the neck caught my sleeve," said Nagelsmann.

"It shouldn't have happened and won't again."

The 30-year-old apologised in person after the final whistle.

Cologne's unwanted record

Cologne are the sixth team in the Bundesliga's history to have two points or less from their first ten games following Saturday's 2-1 defeat at Bayer Leverkusen in the Rhine derby.

All bar one of the six -- Hamburg, who only stayed up last season after winning a play-off -- were eventually relegated.

"If Hamburg can manage it, so can we, although they are used to it - I don't mean that negatively - while this is our first time in this situation," said Cologne coach Peter Stoeger.

Cologne's director of sport Jorg Schmadtke quit on Monday, leaving Stoeger to hope results pick up at home to Hoffenheim next Sunday.