Ancelotti hails 'stupendous' Bellingham after dramatic Clasico win
The England international, who has started his Madrid career in remarkable goalscoring form, unleashed a rocket into the top corner from distance after Ilkay Gundogan had sent hosts Barcelona ahead at the Olympic Stadium.
Bellingham then fired home a second in stoppage time to silence Barcelona fans and reach 10 goals in the top flight this season.
Barcelona hit the woodwork twice and had the better of the game but Bellingham, La Liga's top goalscorer, is in unstoppable form and inevitably made his mark in his first Clasico.
Bellingham's brace sent Madrid to the top of La Liga, ahead of Girona on goal difference, with both teams four points ahead of Barcelona in third.
"He seems like a veteran... the goal to level it totally changed the game," Madrid coach Carlo Ancelotti said of his 20-year-old match-winner.
"What was surprising today was his shot, he's always arriving in the box, today he scored a stupendous goal from in front of the area."
Bellingham has now scored 13 goals in 13 games for Real Madrid across all competitions.
"He can get to 20 or 25 goals, because he has started very well," added Ancelotti.
"We don't have it in our heads that he's a goalscoring striker, we have in our heads that he's a very important player for us."
Barcelona could not believe the points had slipped out of their hands after a strong performance.
"The summary is simple, we had 60 very good minutes where we scored a goal, they had 20 to 25 minutes and they scored two," said coach Xavi.
"I think Madrid's victory today is unjust... they were much more efficient than us, that is the big difference."
Barcelona were boosted by the returns of Robert Lewandowski, Jules Kounde and Raphinha from injury, with Xavi naming them on the bench.
His counterpart Ancelotti once again deployed Bellingham in the number 10 role as he got his first taste of arguably the world's biggest club football match.
However it was another midfielder playing for the first time in the Clasico who broke the deadlock - Barcelona's summer arrival Gundogan.
The former Manchester City man was sharpest when Aurelien Tchouameni intercepted Ferran Torres' pass, diverting it back into his own area.
David Alaba tried to clear but was thoroughly unconvincing and Gundogan read his intentions, hopped onto the ball and swept past Kepa Arrizabalaga in the sixth minute.
Post denies Barça
Fermin Lopez, one of the emerging young Barcelona La Masia academy products who has broken into the first team, slapped a shot against the post after the intense Gavi pressed high to win the ball back.
Madrid defender Antonio Rudiger hammered wide from nearly 40 yards out as Madrid were held off by the hosts, with winger Vinicius Junior getting into tangles with Gavi and Ronald Araujo, deployed at right-back to try and shackle him.
After Araujo barged the Brazilian, he protested, with Xavi telling him it was just a shoulder charge, although the Barcelona coach could not defend Torres' rugby tackle on Vinicius just before half-time, which earned him a yellow card.
Gavi, Gundogan and Lopez controlled the midfield, with Joao Cancelo's more advanced position allowing Barcelona additional defensive security.
Barcelona struck the woodwork again when Inigo Martinez headed Lopez's inch-perfect cross against the post.
Madrid were reduced to long-range efforts but eventually one ripped into the net to level the score, with just over 20 minutes remaining.
Marc-Andre ter Stegen could not keep out Bellingham's blast, pulling Madrid level in a game they had struggled to find a foothold in.
With the game heading towards a draw, Bellingham intervened decisively - in the right place at the right time to shoot through Ter Stegen's legs after Luka Modric diverted Dani Carvajal's cross into his path.
"I'm not someone who evaluates the opposition team, he scored two goals, he did it for Real Madrid and he changed the game," Ter Stegen told DAZN.
"We had it, the game, going in our favour and we didn't know how to keep it that way."
