In the fourth Ruy Lopez, Berlin Variation of the 2014 FIDE World Championship, GM Magnus Carlsen finally broke through the Berlin Wall against former title holder GM Viswanathan Anand.

A mistimed exchange sacrifice was the Indian's demise and allowed the champion to successfully defend his title 6.5-4.5 in the 11th game.

"In general I'm a believer in material, so I like to grab it instead of giving it up," Carlsen said about accepting the offer. "I was pretty happy when he made that move. I thought that he wouldn't have enough compensation."

Anand admitted that his nerves did not hold up as well as other times in the match. "My nerves were the first to crack," he said. "I think [Carlsen] is more stable overall."

Earlier on, Anand had an advantage after blowing open the b-file.

"This day was a real struggle," Carlsen said afterward.

GM Magnus Carlsen after defending his title

Carlsen said that he has been fighting an illness and was relieved to end the match today. He also admitted that the gravity of the game, and the final moments, disturbed his calm: "I got really excited and had to control myself then."

According to Chess.com Director of Content Peter Doggers, the win was the first over the Berlin Wall in a world championship match. The opening gained prominence as a resource for Black in the 2000 Kasparov-Kramnik encounter.

The final moments, where Carlsen said he struggled to keep his composure.

"Today was one of the toughest days of all," Carlsen said. "I didn't particularly want to come back for a 12th game."

He criticized his own play from moves 18-23, which allowed Black to coordinate a scary pawn break on the queenside: "I'm very happy with the way I pulled myself together after that."

The game was much more complicated that the last iteration with the same colors. The two drew rather quickly in round nine, also a Berlin.

Analysis by GM Dejan Bojkov

"It was a very tense position. When I got this ...b5 break, I understood that if he doesn't take, the position remains very tight," Anand said.

Instead of occupying the b-file, another way to play the position was to exchange his bishops for White's knights.

Since computers criticize the move 27...Rb4, what else did Anand consider? He also looked going one square farther with 27...Rb3.

He then analyzed 28. Rb1 Rab8 29. Rxb3 Rxb3 30. Bxa5 Ra3 31. Bc7 Rxa4, "and I evaluated this as equal...I can't say why I suddenly decided to go for this exchange sac...It was a bad gamble and I was punished."

After that unexpected gambit, Team Carlsen began getting excited. Everyone, that is, except for Carlsen's father and manager.

Henrik Carlsen (left) and FM Espen Agdestein look at the +2 evaluation but don't quite believe it yet.

The throng of Norwegian journalists, now numbering about 30, began losing their impartiality. Multiple television crews went live, never wavering their lenses away from these two men.

Some winners of Norway's Noble Prizes don't get this much attention.

Eventually, even Agdestein had to give in to his emotions, knowing that the best player in the world could not mess up the ending.

Carlsen's manager is the last in the room to smile.

Anand played ...Rb4!? Actually this moment came well after the errant rook move.

The two players had a brief discussion on stage following the game. They mostly talked variations such as the ones above. Carlsen said without 27...Rb4 that Black is "doing fine."

He also quite liked his idea of the retreat 29. Nh5, followed by advancing the f-pawn since the bishop on e6 cemented Black's defense. Carlsen said evicting Black's best piece was key.

"Eventually I handled the complications better than him and gained an edge," Carlsen said. At times during the press conference he seemed to have a dry mouth and struggled to get the words out.

Anand added that it was not his original intent to play risky chess. He called his 27th move a "nervous decision."

Later he unveiled himself more than at any time in the more than two-week match. "I wasn't thinking very clear at this point," he said about some of the moves at this point in the game.

The former champion liked how he played with White compared to Chennai, 2013. He said this match was tougher and he played better, but "I had more weak moments than him, and this tended to decide the match."

For the only time in the match, the players answered questions separately.

"In the end, I have to admit he was superior. His nerves held up better...All things taken into account, he just played better."

Carlsen agreed this time around was more difficult overall. He compared today's game to round nine in Chennai, "but I was in greater peril in that game." He said his play in the match was "inconsistent, but good enough."

He also didn't foist hyperbolic attention on the "ridiculous blunders" of game six, since he was better for most of that contest anyway.

The most pressing and touchy topic is often near the end of an interview, but the press corps wasted no time asking Anand about his future plans.

The first question centered on any possible plans to leave top-level chess, but we save it for the end.

Anand thought for two seconds, leaned into the microphone and said "no," whereupon those in attendance clapped for his answer.

As for the "youngster," well, he's not going anywhere of course. His post-match tweet resembles a certain basketball player:

A big thanks to everyone who supported me on this interesting journey. Two down, five to go. pic.twitter.com/Ch5uUOltOF — Magnus Carlsen ( @MagnusCarlsen ) November 23, 2014

You can compare his desire for seven titles to this man!

Even though he loves basketball (even staying up late some nights in Sochi to watch the NBA), Carlsen was probably referring to this man's actual titles, not Lebron's wishful thinking:

Magnus said "2 down, 5 to go," referring to my 7 successful world championship matches. (6.5 really.) I wish him the best of luck! — Garry Kasparov ( @Kasparov63 ) November 23, 2014

Kasparov also tweeted congratulations to his former student.

Contrary to some expectations and reports, Russian Prime Minister Dmitry Medvedev did not arrive for a ceremonial first move. According to AGON Owner Ilya Merenzon, he was held up in Moscow and unable to make it to the match in time.

@nigelshortchess I'm not sure white is better at all. If he wants to win position could easily become double-edged #CarlsenAnand — MVL ( @Vachier_Lagrave ) November 23, 2014

I have touched more levels on my emotional specter to day than I did my entire hicg school career #CarlsenAnand — Kaja Marie Snare ( @kajasnare ) November 23, 2014

Don't let the opening's name fool you - this position is extremely sharp. Give white four free moves, and he's killing black on kingside! — Jon Ludvig Hammer ( @gmjlh ) November 23, 2014

GM Agdestein: "This is a critical position for Anand. b5 is the most spectacular move!" #CarlsenAnand #vgsjakk #nrksjakk — Tarjei J. Svensen ( @TarjeiJS ) November 23, 2014

pretty exciting. Anand pushing for a goal in the 85th minute #CarlsenAnand — Eric Hansen ( @hansenchess ) November 23, 2014

Carlsen-Anand 2014 | Score

# Name Rtg Perf G01 G02 G03 G04 G05 G06 G07 G08 G09 G10 G11 G12 Pts 1 Carlsen 2863 2832 ½ 1 0 ½ ½ 1 ½ ½ ½ ½ 1 6.5/11 2 Anand 2792 2798 ½ 0 1 ½ ½ 0 ½ ½ ½ ½ 0 4.5/11

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