Tottenham are pushing Chelsea all the way in the title race and face their London rivals in the FA Cup semifinals this weekend.
Following on from last season's Battle of Stamford Bridge, it appears English football has a new rivalry. While the teams have hardly seen eye-to-eye in the past, the rivalry has ramped up in the past few seasons with silverware at stake.
ESPN FC's correspondents Dan Kilpatrick and Liam Twomey discuss the clubs' growing enmity.
Dan Kilpatrick: The enmity dates back decades, at least as far as Spurs' victory in the 1967 FA Cup final -- the first to be contested by two London clubs -- with former Chelsea players Jimmy Greaves and Terry Venables in the side. These days, the dislike runs from Tottenham's boardroom to the terraces, right through the team. Most fans will tell you they hate Arsenal for who they are but hate Chelsea for what they are.
Liam Twomey: An entire generation of Chelsea supporters who are now Stamford Bridge regulars grew up knowing that Tottenham were bigger and better. They were also more glamorous, particularly during the prime years of Glenn Hoddle, Osvaldo Ardiles and Ricky Villa in the 1980s.
It wasn't until Hoddle defected to west London in 1993 that Chelsea were able to shake off a reputation for mediocrity with the help of their own sexy overseas imports, but the inferiority complex never really went away.
Instead, with the arrival of Roman Abramovich, it transformed into a relentless desire to gleefully celebrate every Spurs setback on and off the pitch. That's why Tottenham's 27-year winless run at Stamford Bridge is considered such a badge of honour, why the song about Willian refers to him rejecting a move to White Hart Lane, and why last season's shattering of Spurs' title hopes was greeted like a trophy win.
Where does Chelsea vs. Spurs rank in English football's great rivalries?
DK: It's far more competitive than the Merseyside derby but it is still behind the Manchester derby and United vs. Liverpool -- and it is not even Tottenham's biggest game of the season. Even if Mauricio Pochettino and his players want to beat Chelsea more than anyone -- and I'm sure that they do -- every Spurs fan is still more concerned about Arsenal.
LT: It doesn't have the dynastic history or cultural significance of Manchester United vs. Liverpool, and for many years it was undermined by the fact that Chelsea were far more bothered about Tottenham than Tottenham were about Chelsea.
Ask many Spurs fans who their club's biggest rival is and the answer might well be Arsenal, though the events of recent years have ensured that the animosity between White Hart Lane and Stamford Bridge is far more mutual than ever.
DK: Possibly, but I suspect it would require a period of two-club supremacy similar to that of Manchester United and Arsenal from the mid-90s. The "Battle of the Bridge" suggests the rivalry will go to the next level if the stakes are consistently high, particularly if Chelsea can provide a sparring partner for Eric Dier, creating a Roy Keane-Patrick Vieira dynamic. Given Chelsea's history of winning and Spurs' potential, a decade for both at the very top is not out of the question but the Manchester clubs, Liverpool and Arsenal aren't going anywhere, so it is more likely to remain a competitive and highly relevant top-six rivalry.
LT: It's already become the most relevant one, given that we're talking about the two best teams in England right now. Whether it grows to become the biggest depends largely on Tottenham. Chelsea are already established as an elite club. If Spurs can build on their exceptional recent progress and the two teams meet on a more equal footing season after season, tension will increase naturally.
But in order to truly take the rivalry to the next level Tottenham have to hurt Chelsea, either by beating them to the title or winning a trophy at the Blues' expense. The coming weeks and months could present opportunities to tick both of those particular boxes.
DK: The best I can say is that Pochettino respects Antonio Conte. The Spurs manager says he played three-at-the-back for most of last season but his decision to switch to the formation was undoubtedly influenced by Conte. And imitation is the sincerest form of flattery. Among the squads, there are plenty of international connections but even Spurs' Belgians were reportedly left fuming at Eden Hazard's comments about Leicester last season. All that said, Conte is detoxifying Chelsea -- a process that could be accelerated if Diego Costa and Cesc Fabregas follow John Terry in leaving this summer.
LT: Abramovich and Daniel Levy despise each other as much as both sets of supporters, to the extent that it's now impossible to imagine a player of any substance transferring directly between the clubs. Conte and Pochettino have similar qualities and clearly respect each other's abilities and achievements, and I suspect there is a similar dynamic between both sets of players even if they don't like each other.
There is much to admire about the way Tottenham have built themselves up as a club and constructed this team, and most Chelsea fans would love to have Harry Kane or Dele Alli at Stamford Bridge -- but you'd struggle to wrestle any such complimentary thoughts out of their mouths.
DK: The neutrals can support who they want, but another element of the rivalry is the dichotomy in the clubs' approaches. They both, for example, have extremely impressive academies but while Spurs trust young players, Chelsea do not. They are both building a stadium, too, but while Chelsea's will be funded by a billionaire owner, Spurs have stringently cut costs and will continue to do so until their debts are repaid. There is little doubt that Pochettino had the Blues in mind when he referred to "artificial success" recently.
LT: Chelsea haven't been truly likeable since the days of Gianfranco Zola, though Carlo Ancelotti did a lot to temporarily rehabilitate the club's image during his brief spell. Conte is also a charming managerial presence whose unaffected touchline emotion has resonated beyond Stamford Bridge.
It's hard to sell a club with figures like Terry and Costa to the neutral, particularly in comparison to Tottenham's young, dynamic and primarily British core. But Chelsea are at their most watchable since Ancelotti and in Hazard, are blessed with one of the most elegantly devastating footballers on the planet.