A character insists on replaying a game until they manage to win at least one game. They will insist on rematches forever, no matter how much or by how much they have lost. If there is money riding on the game, the character will increase the money in the pot forever until they can win.
Concepts related to this include the Sunk Cost Fallacy (which is a real life motivation for behavior such as this) and the Failure Montage, a common way of establishing the amount of times a character has lost. The character demanding a rematch is almost necessarily either a Sore Loser or a Determinator, depending on whether they refuse defeat out of a shortage in sportsmanship or a surplus in resolve.
It's worth pointing out that in any scenario where the winner is the one who wins just over half of the games played, but the loser invokes this trope to keep things going, it's generally implied the loser has not won once yet, so the loser would have to win literally every single game to follow to be declared the winner. Which also implies the winner has won every single game so far. If the loser hasn't won a single game yet, what makes them think they'll win one now, let alone all the ones needed to be declared the winner?
- Get Backers: During a hot springs episode, a confident Ban Mido challenges sweet and innocent Natsumi Mizuki to a high-stakes ping-pong match and, you guessed it, Hilarity Ensues.
- Ranma ½: Akane suddenly gets much stronger because of some special noodles. To test whether she really had become insanely strong, Ranma challenges her to arm-wrestle him. He loses, but promptly challenges her to another round. This continues until Akane gets bored of it and Ranma is battered and beaten. When she changes back he insists on continually extending it even though he is winning to celebrate.
- In Minami-ke, Kana starts one of these with Fujioka to see who can get higher test scores. He ends up beating her on every test, despite the fact that she changes her scores to make them look higher.
- In A Certain Scientific Railgun, level 5 esper Misaka Mikoto keeps challenging level 0 Kamijou Touma to fights.
Touma: You say duel, but you've lost every time, haven't you?
Mikoto: Shut up! You haven't actually landed a blow on me, so I haven't lost.
Touma: When's this gonna end, then?
Mikoto: Obviously, when I win.
- In Heaven's Lost Property, Tomoki is humiliated after scoring the lowest in a trivia game show. In an attempt to prove he isn't dumb, he challenges The Ditz Astraea to a game of Go, but she easily wins. He angrily challenges her to more games, degenerating from Shōgi to foosball, video games, baseball, etc. with Nymph lampshading that the later games don't prove intelligence. Astraea wins 26-25.
- Food Wars!: In his attempt to convince former 3rd Seat Megishima to join the Rebels against Central, Soma decides to challenge him to culinary battle after culinary battle, insisting on going on "until he gives up". Despite losing every duel, Megishima notes that Soma never gave up and declares him the winner, and agrees to join them upon out of respect for how much of a Determinator he is.
- In Azrael Annual #2, a Legends of the Dead Earth Elseworld, Two-Face does this to himself. When Azrael meets him, he's standing at a crossroads tossing a coin to decide if he is good or evil. We're not told what answer he wants, but Azrael leaves him going "Two out of three ... no, three out of five ... no..."
- In the Darkwing Duck comic "Super Union Blues", Launchpad sends Drake through this trope to snap him out of a 10-Minute Retirement.
- "Sore Players" from the "Family Tree" issue of The Loud House has Lynn and Lynn Sr. engaging in one of these while playing Jenga. The contest lasts through the days and into the night, when the tower gets knocked over right when they were about to have a tie-breaker by Cliff the Cat. Having grown tired of Jenga, they decide to move the competition to video games.
- In one Madam & Eve strip, Madam and Eve play rock-paper-scissors for Eve's annual salary negotiations. Eve keeps winning, and Madam retorts with "Best out of 45!"
- In the Bleach fanfiction Uninvited Guests, Kyoraku uses his Shikai against Soi Fon, forcing them to play a children's game, and whoever loses gets stabbed. Sounds fair? It can declare as many rounds as it wants. Sounds broken? It doesn't care if its master is winning or not. It saves Kyoraku after Soi Fon wins at ping-pong by declaring best two out of three, but it blocks Kyoraku after he wins two out of three. Kyoraku loses in the end.
- Invoked in A Thing of Vikings when Snotlout tries to challenge Hiccup in a three-stage contest of strength, speed and wisdom; even after Snotlout lost the first two rounds (Astrid fought on Hiccup's behalf due to his lost leg and Hiccup and Toothless beat Snotlout and Hookfang in a race), he still tried to insist on taking the third test, which actually got him declared the loser of all three rounds as he didn't show the wisdom necessary to recognise that winning that round wouldn't have made a difference and he would have been tested in his weakest area anyway.
- In Toy Story, with Mr. Potato-Head, losing at Strip Battleship with Hamm, says "How about three out of five?" after losing his nose.
- After the Minor Kidroduction of Tangled, we come across Rapunzel playing hide-and-seek with Pascal - which Rapunzel wins handily.
Rapunzel: That's twenty-two for me... How about twenty-three out of forty-five?
- In Bill & Ted's Bogus Journey, the title characters attempt to win their freedom in a game of Chess with Death in a sequence reminiscent of The Seventh Seal. Only instead of chess, the boys play Twister, Battleship, and a variety of other contemporary games, which Death keeps losing. (Of course, Death doesn't want to admit he's losing to these airheads, so he keeps altering the conditions of the challenge, making it "best 2 out of 3", "best 3 out of 5" and so on...) This is actually used as a plot point in the original script, which was used for the comic book adaptation. At the Battle of the Bands, Bill and Ted are repeatedly killed by their robotic Evil Counterparts, and they make Death bring them back each time, citing the number of games at which they beat him. The Novelization drops the number of resurrections to 2, saying he (Death) owed them one life per game (so 4)
- Daredevil (2003): A darts player in a pub asks "Best of three?" after being beaten by Bullseye, who scored four bullseyes in a row.
- An inversion in Ender's Game: Ender challenges an older student to a game, but immediately states that he is going to win two out of three. The student wins the first match and tries to claim victory, but Ender convinces him that there's no pride in winning once against someone who've never played that game before and proceeds to win next two matches.
- In My Next Life As A Villainess, the young Prince Alan challenges Catarina to a "fight," which ends up being a tree-climbing contest. She wins effortlessly, but he keeps coming back for rematches, and continues to lose. He fails at every attempt until she decides to switch to a piano-playing contest (partly because her mother doesn't approve of her climbing trees). Things take a less humorous turn when her proclaiming him the obvious winner at piano-playing only makes him insist she's making fun of him, and it turns out he has a major inferiority complex over his brother Jeord, who's ridiculously good at everything.
- A variation appears in an episode of Frasier in which Frasier learns that Martin is a better chess-player than him; no one actually says 'Best out of (however many)', but Frasier won't stop forcing Martin to play chess until he wins a game.
- An episode of the original serial The Addams Family has Gomez lose to Morticia in every possible match (from fencing to chess), reaching ludicrous numbers.
- The Double-or-Nothing variant pops up in an episode, ultimately culminating in Monica and Rachel losing their apartment (and mattresses) to Chandler and Joey.
- Monica and Phoebe's future-husband Mike are driven to play ping-pong out of boredom. It is revealed that they are both as competitive as each other, and the game gets more and more frenzied as Monica's hair gets bigger and bigger. Chandler's better than both.
- Serious and odd variant in Farscape, where the doubled Crichton(s) play rock-paper-scissors over and over again, in complete silence, hoping to not tie with each other and prove they're not identical.
- Played with on the old Disney show The Jersey. Nick and Cole competed in a series of strange athletic challenges of their own device, with wins trading back and forth. Every time they had a clear winner, the clear loser would raise the numbers again, then (presumably) win the next two events.
- On Monty Python's Flying Circus, a squad of World War I soldiers is Drawing Straws to see which of them shoots himself. After losing twice, the captain insists on going "best two out of three".
- In Scrubs, the janitor makes an unlikely flick of cotton balls across the desk. Kelso bets he can't repeat the trick, which the janitor accepts. After failing, he keeps betting double or nothing, to the point that he owed Kelso hundreds of dollars, until the end of the episode where he makes it. "We're even, good night sir."
- Seinfeld had the double-or-nothing variation when Elaine kept betting Jerry that she was broken up for good with Puddy. Several rebounds later, she gives up, stops betting, and Puddy breaks up with her.
- Happens in Corner Gas when Emma tries to reclaim some money her husband gave to Hank by challenging him to a game of pool. Hank brags that he's really good at pool and that it wouldn't be fair to Emma, making it seem like it's going to play out as a Break the Haughty scenario where Emma stomps Hank flat, but in the next scene we find out that Hank beat Emma 10 games in a row. When Emma requests "best 11 out of 21", Hank just gives her the money so that he can finally go home.
- In April of 2004, Hailey Hatred and Christie Ricci started what became a "best of 1,000" series, at least in Hatred's mind anyway. It had to be spread across multiple feds as no single promotions ran enough shows to settle it in a timely manner. She also finished off Hex at a BBW event on July 13th with a super brain buster to win their 'best of seven'.
- In The Men from the Ministry, while the supercomputer CECIL is being installed on the General Assistance Department One and Two have ended up in a series of chess-matches against the Foreign Office, with the Foreign Office having won the first 60 games. During the episode the Foreign Office wins the 61st game, but at the end of the episode CECIL manages to defeat them 10 times in a row.
- The Wotch takes it to an extreme: "Alright, best five hundred fourteen out of a thousand twenty seven!"
- Tower of God: On the Hell Train, Khun promises to face Rachel in a contest where he's not inherently better than she is in every respect... so they toss a coin, to see who God wants to win. After she loses, she insists that Khun must have cheated (somebody notes that this was probably true, but he couldn't do it a second time) and wants to ignore that result and try again. He concedes and loses. But after she just wanted a rematch, it's easy for him to insist on making it best two out of three instead.
- In one Red vs. Blue episode, Grif tries to invoke this on Caboose with The Quiet Game, clearly trying to get him to shut up. Caboose being Caboose, however, it doesn't really work.
Caboose: It's like you're not even playing at all!
- Star tried to put the trope in effect in attempt to pull amazing plays in Jerma985's 'Pulling It Off with The Pump Brothers' after he keep dying for dumb reasons(dying to a mini sentry, dying to a guy who build said mini sentry with a crit Frontier Justice and to a random huntsman) but Jerma subverted it by the third time he died by forcing himself in the game and added a new rule to see which of the two pulls off first. No hundred bucks betted. They never pull anything off in the remaining clip.
- Rugrats did this trope straight-up, with Angelica (not quite understanding the math involved) challenging Susie to "two out of five", "two out of nine", and "two out of fourteen". After she finally wins one game, she excitedly says "Now all I have to do is beat you fifty more times, and...."
- Happened in The Flintstones with a coin toss over a winning cruise ticket (only good for two people), except it kept being extended by the *winner* who felt sorry for the losing couple. Eventually, the two ladies ended up going together.
- The same variant as in Frasier occurs in the Chowder episode "The Cinimini Monster": Chowder and Mung are held captive by the titular monster, and are forced to play board games and win to be freed. However, whenever one of them gets ahead of the monster, he immediately throws the game off the table and switches to a new one. When Truffles is called in to beat the monster (which she does) he locks up the house and swallows the key.
- Hey Arnold! once featured the title character challenging a man living in the city sewers to a game of chess with the plot's MacGuffin serving as reward. Arnold wins every game with the sewer man eventually demanding "Best 8 out of 15" games.
- My Little Pony: Friendship Is Magic
- In "Dragonshy", Rarity and Pinkie Pie play Tic-Tac-Toe while waiting for Applejack and Fluttershy, with Pinkie Pie winning 35 straight games. Rarity grumbles about this, then brightly proposes, "Best of seventy-one?"
- In "Castle Sweet Castle", Twilight is trying to avoid staying in said castle and keeps challenging Rainbow Dash to races. (Unusually for this trope, she doesn't actually care about winning - she just wants something to do that'll keep her away from home.)
Rainbow Dash: She just kept going! Best out of ten. Best out of twenty. Best out of a hundred!
- The Legend of Korra: When Asami and Bolin start playing Pai Sho to pass the time during a stakeout, she turns out to be much better at the game, leading to Bolin repeatedly rematching her. Bolin does seem to be improving as they continue, and they eventually get to a game where Asami thinks he may finally beat her, but then Pabu jumps on the board and scrambles all of the tiles.
- Occurs at the end of the Johnny Test episode "The Enchanted Land of Johnnia" after Johnny and Dukey find out they were actually in a virtual reality game. Johnny's sisters win and Johnny challenges them to rematches twice with the usual "best two out of three" and "best three out of five"... but after he and Dukey win the first time, the girls challenge them to "best four out of seven." They could've just won the next game to beat Johnny and Dukey's last challenge instead of making it harder for themselves.
- In one episode of Danny Phantom, Jack and Maddie kept playing games. Jack, who kept losing, suggested "best 2 out of 3", "best 3 out of 5", and so forth.
- In one Timon & Pumbaa short, Timon sets up a Shell Game on the sidewalk (which was also a set up). When the first guy who walks up wins the game, Timon suggests "best two out of three?" but the guy wins again. After a few iterations of this, the scene jumps to sometime later when the number of rounds is well into the triple digits. Then they get caught by a cop for gambling.
- The Dilbert animated series had the Pointy-Haired Boss insist on a best three out of five after losing a pair of chess games against a pineapple.
- During the mid-episode clips on Xavier Riddle and the Secret Museum, Xavier often attempts to beat Berby in a round-the-world portal race. Despite his use of various vehicles and gimmicks (e.g. a chariot, Leonardo da Vinci's wingsuit), he's apparently lost about a hundred such races before, yet is still 100% convinced that this time will be different.