The 18-year-old was unhappy after the 3-2 loss at Signal Iduna Park, with referee Felix Zwayer awarding Bayern a late penalty for handball against Mats Hummels, which was scored by former Dortmund man Robert Lewandowski to seal the win for the visitor.
❌ NO PENALTY!! What do you think? The hosts are NOT happy 😡@BVB 2-2 @FCBayern— beIN SPORTS (@beINSPORTS_AUS) December 4, 2021
Watch LIVE via @kayosports, @Foxtel, Fetch and beIN SPORTS CONNECT!! ▶️ https://t.co/dR3JmGUdy7#DerKlassiker #BVBFCB #Bundesliga
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Zwayer had also turned down a penalty appeal from Dortmund earlier in the game after Marco Reus went down under a challenge in the box.
Interviewed after the game by Viaplay, Bellingham said: "For me, it wasn't [a penalty]. He [Hummels] is not even looking at the ball and he's fighting to get it and it hits him. You can look at a lot of the decisions in the game.
"You give a referee that has match fixed before the biggest game in Germany. What do you expect?"
⚽️ GOAL!! Insult to injury for @BVB, given no VAR was used earlier for its own penalty appeal.@BVB 2️⃣-3️⃣ @FCBayern— beIN SPORTS (@beINSPORTS_AUS) December 4, 2021
Watch LIVE ▶️ https://t.co/dR3JmGUdy7#DerKlassiker #BVBFCB #Bundesliga
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The England midfielder's comments referred to Zwayer's six-month ban for his involvement in a match-fixing scandal in 2005, which centred around fellow official Robert Hoyzer.
The DFB released a statement on its website on Tuesday saying: "The Sports Court of the German Football Association (DFB) has fined Jude Bellingham in the amount of 40,000 euros in single-judge proceedings after indictment by the DFB Control Committee for unsportsmanlike conduct.
"The player of the Bundesliga club Borussia Dortmund has already agreed to the verdict, the verdict is therefore legally binding."
Zwoyer has explained the two controversial decisions, telling Sky Sport: "[The Reus incident] was contact in the upper body area, which is allowed to happen even at high speed.
"The situation is not black and white. I decided against the penalty kick because of my line [of sight]. It was not necessary for me because I had a clear view.
"Again, in the situation with the handball on Hummels, I had a factual perception. In the other situation, I had a complete view. If the video assistant had a second shot – like an arm that was out – he would have given me that on the ear.
"The [Hummels] situation was a standard corner kick. I see in the running game that it's about a touch by Hummels. In the game, it was not clear whether the arm went to the ball.
"I checked it after [the VAR team], then the arm position was checked. In the end, he clearly deflected the ball with his elbow. I came to the decision in the end that it was a penalty."