Five observations from the weekend's Bundesliga action

Here are five talking points from the weekend's Bundesliga action:

Heynckes' ticking off

Lewandowski netted his 150th competitive goal in 193 games for champions Bayern Munich in Saturday's 3-1 win at Cologne -- but was reprimanded for his attitude.

After hitting his 29th league goal this season, the hot-shot striker was unhappy at being substituted for Sandro Wagner on 77 minutes, ignoring Heynckes as he trudged off.

"The Bayern coach decides the substitutions and every player has to hold to that," said Heynckes.

"I'm the boss -- and nobody else."

Lewandowski has nearly twice as many goals as his nearest rival in the quest to be the Bundesliga's top-scorer this season.

His 29 league goals makes him Europe's third best goal-scorer behind Barcelona's Lionel Messi, who has 33, and Liverpool's Mohamed Salah with 31.

Lookman boosts Leipzig hopes

Ademola Lookman, who is on loan from Everton until June, boosted his chances of staying at RB Leipzig with two goals in a 4-1 drubbing of relegation-threatened Wolfsburg.

Starting as an attacking midfielder, the 20-year-old Englishman converted a cross, then banged home RB's second after pouncing on a mistake.

Lookman, who arrived in January, has said he wants to stay at Leipzig and the club hope to keep him.

"I think he has huge potential and he's done really well for us since he came," said Leipzig's coach Ralph Hasenhuettl.

"It was a really important transfer and I hope the last word hasn't been spoken on the matter just yet."

Leipzig are sixth, but can still win a Champions League spot by finishing fourth if they beat Hertha Berlin on Saturday and both Leverkusen and Hoffenheim lose.

Sane's parting gift

Senegal centre-back Salif Sane marked his final home game for mid-table Hanover with a rare goal in Saturday's 3-1 win against Hertha Berlin.

The 27-year-old headed home from a free-kick in Hanover after signing a four-year deal to join Schalke.

"Great atmosphere, great team," said Sane.

"I didn't plan to score, the most important thing was the three points and it was nice to get the goal."

After five years with Hanover, Sane can look forward to Champions League football with Schalke next season, but wants three points in his final game at Leverkusen on Saturday: "the most important thing is to win the last game."

'Runners-up' Schalke celebrate

A 2-1 win at Augsburg secured second place in the Bundesliga for Schalke and a Champions League place for the first time in three years.

"Runners-up, runners-up!" was the tongue-in-cheek chant from the away dress-room with Schalke a massive 24 points behind champions Bayern Munich in the table.

Their coach, Domenico Tedesco, can dream of playing the likes of Barcelona or Real Madrid just 12 months after staving off relegation with Erzgebirge Aue in Germany's second division.

"You can feel that something is coming together here, but the journey isn't over," said Schalke's director of sport Christian Heidel.

The challenge for next season will be to replace Germany midfielders Leon Goretzka, who has signed for Bayern, and Max Meyer, who is out of contract and yet to announce his future club.

Rode in hot-water

Borussia Dortmund midfielder Sebastian Rode is in hot water for suggesting coach Peter Stoeger is on his way out.

"The impression he makes in the dressing room, gives us firm reason to believe we will get a new coach next season," Rode told Sky on Sunday.

Stoeger has a contract only until the end of the season, but it has not been confirmed whether he will stay or go.

"We will definitely bring Sebastian into line and sanction him," said Dortmund's CEO Hans-Joachim Watzke, especially after Rode suggested Swiss coach Lucien Favre, currently at French side Nice, would be a good replacement.

Stoeger broke Dortmund's nine-match winless streak last December when he replaced Peter Bosz.

They need a point at Hoffenheim on Saturday to secure a Champions League place next season, but have been inconsistent, slumping to a shock 2-1 defeat at home to Mainz on Saturday.