LONDON -- Three observations from Tottenham's shocking 5-3 London derby win against Chelsea at White Hart Lane.
1. King Kane ravages Chelsea
Glory, glory Tottenham Hotspur, and confirmed is the king of White Hart Lane. Spurs striker Harry Kane, with two goals and one assist and a performance of boundless drive, took apart Chelsea and knocked them off their perch. A mathematical miracle sees both Chelsea and Manchester City with identical records.
With Chelsea leaders at Christmas, but now having to share, manager Jose Mourinho's expression was one of barely contained rage. Opposing manager Mauricio Pochettino, meanwhile, has turned Tottenham into a proposition with a significant role to play in the battle for Champions League qualification.
When striker Diego Costa scored in the 18th minute from close range after midfielder Eden Hazard hit the post, and Oscar had provided the assist on the rebound, it looked business as usual for Chelsea at a ground they usually enjoy visiting.
Yet by the 52nd minute, a Mourinho team had conceded four Premier League goals for the first time ever, and Tottenham were delighting in their finest evening since Inter Milan were smashed 3-1 in the Champions League in November 2010.
Back then, Spurs had star winger Gareth Bale as their inspiration. Now they have Kane. His goals were taken with supreme confidence, while he won a penalty by foxing befuddled centre-back Gary Cahill into committing a clumsy foul. Winger Andros Townsend converted with an unlikely ice-cold calm. Attacking midfielder Christian Eriksen, on the other hand, is a playmaker of a quality to make superclubs sit up and take notice; it was his excellence that set up Danny Rose's goal in the 44th minute to make it 2-1 at that time.
Eden Hazard's interchange with Cesc Fabregas made it 4-2, and Chelsea wanted a red card for a challenge on Hazard by Federico Fazio that was actually a fair tackle. But Kane seized back the initiative by playing through Nacer Chadli for Tottenham's fifth, as the roof blew off White Hart Lane. Victory was held on to, despite John Terry's late goal in the 87th minute. The glory was Tottenham's, and the title race is as tight as is possible; welcome to 2015.
2. Chelsea wobbles?
Frank Lampard kept the hammer down on Chelsea with his winner for Manchester City against Sunderland, and might be torturing his former club for the rest of the season after a New Year's Eve's loan extension from their MLS affiliate club, NYC FC.
City have kept on Chelsea's coat-tails without ever reaching their heights of last season. It must be of concern to Mourinho that his rivals have not hit top gear, and his own team's early-season purple patch has not resulted in a significant gap.
New Year's Day saw the Premier League turn for home, and any retrospectives of the season so far would have a team of the half-season decked with Chelsea players, but perhaps only David Silva from the defending champions.
Terry, Cesar Azpilicueta, Nemanja Matic, Fabregas and Thibaut Courtois, give or take Manchester United's David de Gea, have been outstanding players in their positions, while Costa battles it out with Manchester City's Sergio Aguero for top striker and probably shades it on grounds of having sustained his fitness. A lack of serious injury problems have lent Chelsea a greater coherence, but they have not been able to blaze a trail away as they did during Mourinho's previous title-winning campaigns in 2004-05 and 2005-06.
Such realisations may be behind Mourinho's tetchy Christmas behaviour. A weakness in Chelsea this season is that they sometimes struggle to hang on to leads. That usually coincides with Matic's energy levels dropping. This time, Tottenham struck back quickly.
Mourinho was visibly annoyed on the sidelines after Kane's first goal and the period of thrilling Spurs ascendancy that followed. All three first-half goals had their genesis in the anchor position that Matic mans for Chelsea. He ended up overrun by Tottenham's young fliers.
Forget that talk of diving and conspiracies against his team; Mourinho's real concern is that his team is not playing with its previous authority. Tottenham located what suddenly looks a highly soft centre. After watching Townsend convert a first-half injury-time penalty, Mourinho billowed straight down the tunnel in visible rage. His evening did not get any better.
3. Doing it for the kids
When midfielder Ryan Mason damaged a hamstring and limped off in the 14th minute, it broke up a five-man band of Tottenham youth products. A growing theme of Pochettino's regime is the flourishing of homespun talents, in a similar style to his Southampton tenure. All three of his first-half scorers made their bones at Spurs' academy.
Rose, at last, looks ready to forge a Spurs career for himself at left-back. Mason may now be absent for a while, but has made himself a first-teamer the last three months. Nabil Bentaleb, just 20, is a central midfielder of huge promise, while Townsend is enjoying a recent run in the team after recovering from the injuries that kept him from playing at the World Cup. Kane, though, is first among youth-team equals leading Spurs' revival.
Of the 100 million-pound-plus outlay from the summer of 2013 that produced the now-popular transfer window phrase "doing a Tottenham," only Chadli and the excellent Eriksen started the match. The Belgian midfielder Chadli, who once looked one of the least likely of that class of 2013, has announced himself this season as a genuine threat.
Ultimately, it was Kane's heroics that sealed Thursday's win for Tottenham. He strolled with untrammelled confidence around the White Hart Lane turf, and is prepared to back himself when openings arrive. Chelsea never dealt with his clever positioning. Uncomplicated, he is currently a joy to watch.
Long may that continue.