All form goes out the window during derby matches.
That is especially true of games between Arsenal and Tottenham, which are some of the fiercest and most exciting clashes in all of European football.
North London's arch rivals will once again meet at the Emirates Stadium in both sides' first FA Cup match of the season. One team will suffer an embarrassing derby loss and an early exit from England's premier cup competition.
Let's look back at some of the best matches in the rivalry's history.
Arsenal first clinched the title at White Hart Lane in 1971, a year in which the Gunners would coincidentally go on to replicate Tottenham's feat of winning the double.
The visitors only needed a goalless draw to clinch first place, and Ray Kennedy's late goal ultimately decided who won the league that season.
A short time later, Spurs lost the distinction of being the only English team to win the First Division and FA Cup in the same season.
On April 14, 1991, Tottenham sealed one of their best ever victories over the hated Gunners.
The scoring was opened by Paul Gascoigne, who ripped in a thunderous 30-yard free-kick to send the Spurs supporters into ecstasy.
A Gary Lineker tap-in was answered by Arsenal's Alan Smith, but Lineker scored a marvelous second to seal the game for Tottenham and secure their passage to the FA Cup final.
Keep in mind that Arsenal had already clinched the First Division title, losing only once all season in the league.
Spurs would win the cup a month later, the memory of their famous derby win etched firmly into their minds.
There has been an illustrious history of north London Derbies in the history of the Premier League, and this one got things started.
Everyone focused on Teddy Sheringham, who was playing in his first match against Arsenal in Tottenham's colours. But Paul Allen scored the only goal of the game, giving Spurs the victory and temporary bragging rights.
The match was not indicative of how the two teams would perform in subsequent Premier League seasons.
Before Ian Wright became a below-average pundit and Jurgen Klinsmann managed Germany and the United States' national teams, they faced each other in a North London Derby when they were at their peaks.
Both strikers were chasing the golden boot trophy and wanted the distinction of scoring 30 goals in a season.
And both scored, but the spoils were shared between the teams. Klinsmann would go on to be named player of the year.
Chasing an unbeaten season, Jens Lehmann gave Tottenham a chance to draw the game late by conceding a penalty that Robbie Keane duly converted to equalise.
But at the end of a batty match that saw Arsenal squander a two-goal lead during their best season ever, the Gunners clinched the Premier League title on the soil of their most hated rivals and continued their ultimately successful quest for an undefeated campaign.
This match could hardly have been more legendary.
Celebrating an historic achievement in such a hostile environment must be an utterly intoxicating and unique feeling.
In the best possible follow-up to Arsenal's title-clinching draw earlier in the year, the Gunners and Tottenham furiously traded blows right up until the final minutes of this game.
Most North London derbies are high-scoring affairs, but nobody expected a nine-goal epic at White Hart Lane that saw both sides throw all caution to the wind and express their true attacking natures.
To realize how utterly insane this match was, consider that the score was only 1-1 at half-time. The seven—yes, seven—other goals were all scored during the second half.
Whenever you thought this game was over, it delivered more twists and turns. Even a Robert Pires goal in the 81st minute could not help Arsenal see the game out comfortably; Frederic Kanoute struck the game's final blow seven minutes later to ensure the nerviest of finishes.
In one of the most memorable matches of the 2008-09 season (and possibly of the entire Premier League era), Tottenham held Arsenal to an eight-goal draw at the Emirates.
Oh, and did I mention that Tottenham were in the relegation zone when the game was played? And that it was Harry Redknapp's first game as Spurs' manager?
How's that for an initiation, Mr. Redknapp?
The most memorable moments from this insane fixture are ex-Arsenal man David Bentley's 40-yard volley over Manuel Almunia and Aaron Lennon's equaliser just before the final whistle.
This match is really the exemplar of the high-octane affairs that the past several North London derbies have been.
Arsenal had a comfortable 2-0 lead on their rivals, but, as they so often have in recent years, the Gunners collapsed and handed three points to their opponents.
When Gareth Bale got one back shortly after the break, the wheels started to come off.
Arsenal were sitting pretty near the top of the table when Spurs travelled to the Emirates Stadium in November, 2010. Tottenham had never won at the Emirates, so no problem for the Gunners, right?
Cesc Fabregas inexplicably threw his arm up to block Rafael van der Vaart's free kick in the penalty area, and Younes Kaboul capitalised on Arsenal's weakness from set-pieces to head home the winner.
Cue madness in the blue half of North London and talk of a power shift.
Speaking of supposed power shifts, Arsenal roundly quashed any notion that Tottenham were finally unseating them as North London's best in this pivotal fixture from two seasons ago.
Down 2-0 early on, the entire stadium was baying for Arsene Wenger's head. Humiliation against their most bitter enemies would have been too much for Arsenal's beleaguered fanbase to take. Online communities of Gunners fans would nearly have imploded.
Then, a bit of magic happened—a touch of the miraculous that only occurs in the most important derby matches.
Arsenal scored five unanswered goals to emphatically drive their unwelcome visitors back to White Hart Lane in despair. What started with an emphatic Bacary Sagna header was finished with a bang by a Theo Walcott brace.
The Gunners once again proved that no power shift was occurring north of the Thames and took the first step toward overcoming Tottenham's 10-point lead.
Arsenal had not spent a penny in the summer transfer window and Spurs had spent over £100 million. Arsenal were in a state of collapse after losing to Aston Villa on opening day and no one knew that the club were about to sign Mesut Ozil.
So when Arsenal did just enough to beat Tottenham at home in a thrilling 1-0 victory, perennial talks of a power shift from red to blue were quieted, if not extinguished.
Arsenal have since risen to the top of the Premier League and left Spurs far behind. Tottenham will undoubtedly be seeking revenge for a humiliating defeat.