After a lengthy series of draws and building tension over the past 11 days, the deadlock at the World Chess Championship was finally broken Monday evening. The defending champion and world No. 1, Magnus Carlsen of Norway, was bested and resigned after 52 moves and five hours of play. His challenger, Sergey Karjakin of Russia, a heavy underdog coming into the match, now leads 4.5 to 3.5 in this race to 6.5 points and chess’s ultimate crown. Karjakin, who began the match ranked No. 9, has inched up to No. 6 in the world.

The advantage in Monday’s Game 8, played on a frigid day in lower Manhattan, swung wildly back and forth between the two players. The game featured back-to-back blunders and a last-second move with the clock’s final seconds ticking down, a scenario worthy of a classic NCAA Final Four game. In the end, Carlsen overextended his reach, wandering into endgame territory more dangerous than he’d realized. Karjakin eventually steeled himself, as he’s done in a number of previous games, and found the winning line.

In the opening, Carlsen, playing as white, deployed something called the Colle-Zukertort System. In this opening, “white develops pieces behind its pawns, then takes action on his own terms,” Robert Hess, a grandmaster and chess.com contributor, told me. In other words: White’s position could get quite intricate before the fight begins, as he gets his pieces just where he wants them. “White tries to release tension on his terms so that his pieces can flourish.”

By about the 25th move, it was clear that time was going to be a factor in the game, as the players struggled to deal with the insanely complex board they’d created with all those flourishing pieces. (Karjakin later called the position “crazy.”) The players get 100 minutes to start the game, 30 bonus seconds after each move, and 50 minutes when they make their 40th move. On the 32nd move, Carlsen had six minutes remaining on his clock and Karjakin had five. On the 34th move, the time ticking, Carlsen (white) faced this position:

He pushed his pawn up to c5, instantly giving Karjakin his biggest edge of the entire match, according to the chess engine Stockfish. After the two traded the rooks at the top of the board and the Russian captured the Norwegian’s pawn on c5 with his knight, the position belonged to Karjakin and his two unimpeded pawns on the board’s left side, itching to become queens. The game was won.

But Karjakin had been burning through his time, which ticked down to less than a minute for five moves in a row. (If a player runs out of time he loses.) He relied on the bonus 30 seconds, burned them down, made a move, received 30 seconds in return, and then burned them down again. It was torturous to watch. In chess, thanks to the 30-second increment, you can relive ulcerous final seconds over and over and over again. The crunch got to Karjakin, eventually. He misplaced his queen on the 37th move, ceding back to Carlsen all of the advantage. One blunder cancelled out another, and the game was level again.

With seven seconds left on his clock — seven seconds until instant defeat and devastated title chances — Karjakin made his 40th move.

Things calmed down for a while after that, both players comfortably pondering the game with their added time. Stockfish saw the endgame as level, or maybe just a touch better for black, until the 51st move. Carlsen (white) had to make a decision here:

He slid his queen over to e6. Karjakin pushed his right-side pawn to h5, heading down toward the white king’s defenses. And thanks to Karjakin’s innocent-looking pawn move, Carlsen had, essentially, run out of useful things to do. The black pawn on a3 was sprinting toward queendom while the black queen and knight were menacing the white king. One move later, Carlsen resigned and the two players shook hands.

After his loss, a distraught Carlsen brushed past a would-be postgame interviewer without a word. As Karjakin dutifully did interviews backstage, Carlsen came out onto the stage for the press conference. But the timing was off. There was no moderator, no Karjakin, no questions being asked. It was just Carlsen, sitting alone on the stage in silence, facing a thick phalanx of expectant reporters, photographers and chess fans. You could pierce the awkwardness with the top of a bishop. And he sat and he sat and he sat, for minutes that felt like hours.

Eventually, Carlsen had enough. He threw his hands up in disgust, stormed backstage and never returned.

FIDE official statement: Magnus Carlsen declined to attend the press conference https://t.co/hvVQYwQPsP #CarlsenKarjakin pic.twitter.com/CIqv9jToPY — Vladimir Savić (@firusvg) November 22, 2016

“Chess is everything: art, science and sport,” the former world champion Anatoly Karpov once said. With the ticking clock and dramatic swings, it had never felt more like a sport to me than it did Monday night. And in sport, the equipment matters. The brilliancies and blunders are born in the minds of the two geniuses vying for this title, but they’re expressed to the world via more mundane physical objects. I wanted to know the tools of these sportsmen’s trade. Consider this your guide if you’re hoping to build a chess arena of your own at home.

The official chess clock of the sport’s governing body FIDE — the small plastic box that loomed over Game 8 — is the handsome maroon model DGT 2010. It goes for about $80.

The championship uses a souped-up board with sensors in the pieces, so that moves can be instantly related to spectators on monitors in the venue and on the internet. But you can buy an essentially identical version, sans sensors, for $470. It sports a rosewood and maple board and ebonized boxwood pieces, and was designed by the Pentagram architect Daniel Weil. The size of the pieces are, apparently, proportioned to the pitch of the facade of the Parthenon.

But, most importantly, in what do the grandmasters sit? Chairs are important to chess players, for obvious reasons. In this year’s match, the two grandmasters have sat — minus the odd bathroom break and so forth — for about 68 total man-hours.

Chairs have a storied history at the world championship. Bobby Fischer famously demanded that an Eames Time-Life Chair be shipped to Reykjavik for his 1972 championship match against Boris Spassky. He said he thought better while sitting in it. An Icelandic chess official thought it’d be nicer for the cameras if Spassky had a matching chair, so one was driven by limousine to John F. Kennedy Airport and put aboard the first flight to Iceland. The model of chair, now an icon of 20th-Century design, thanks in part to the match that had a rabid viewership in the States, is now sold by Herman Miller for $3,000.

And what about this year’s model? After a Zapruder-esque examination of photographs from this year’s match, a lengthy search of office chairs online, and a crowdsource of my social networks, this year’s chair appears to come from Staples, the office-supply chain store. It’s called the Baird Bonded Leather Manager’s Chair and it retails for $270. Both players appear to use the same model. (Multiple messages to FIDE and its partner Agon Limited asking about the chairs were not returned.)

The two grandmasters will take their seats for at least two — and up to four — more hours-long games. There could be further shorter games if the match is tied after that. They should both get comfortable in their Staples chairs. Kirill Zangalis, Karjakin’s manager and a spokesman for the Russian chess federation, addressed the press after the game. “Sergey now knows how he can win this match,” he said. “Now, it’s only the beginning.”

Tuesday is a rest day, and Game 9 begins Wednesday afternoon. I’ll be covering the rest of the games here — although there will be no dispatch here on Thursday — and on Twitter.