Jose Mourinho's Tottenham were well beaten on their last visit to Stamford Bridge. That February defeat - a 2-1 loss which could easily have been worse - proved costly in their hunt for a top-four finish.
It was also a difficult one to take for the man in the dugout. Mourinho versus Frank Lampard was billed as master versus apprentice, but it was the latter who came out on top - and only three months after Chelsea had won at the Tottenham Hotspur Stadium too.
It is Mourinho, however, who will take the most satisfaction from their latest reunion in west London. Sunday's goalless draw ensures Spurs remain top of the Premier League table for another week and gives them four points from a possible six in back-to-back meetings with Manchester City and Chelsea.
It also adds to the growing sense that Mourinho's men might have a genuine title challenge in them this season. They lacked the cutting edge shown against City last weekend, but the rest was all there. Chelsea were stifled for long periods, mustering only three shots on target and rarely threatening in a meaningful way.
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"You can tell us we didn't have many chances, and I agree, but how many did they have?" said a smiling Mourinho in his post-match interview with Sky Sports.
Spurs have now accrued nine points more than at the same stage of last season and conceded the fewest goals in the Premier League.
As well as beating Manchester City at home and holding an in-form Chelsea side at Stamford Bridge, they have thrashed Manchester United at Old Trafford. They have not tasted defeat in the Premier League since their opening day loss to Everton.
Sunday's draw was another step in the right direction and it was achieved with what Sky Sports pundit Roy Keane described as a "typical Mourinho-type performance". Spurs were compact, disciplined, and, in the first half at least, full of menace on the break, ready to pounce on Chelsea errors and spring forward at speed.
It is a testament to the progress of Mourinho's Spurs project that his players are now able to fulfil his tactical demands as well as they did at Stamford Bridge. Last season was a transitional one, but they certainly look like a Mourinho side now and it's partly down to a change of mindset.
"A draw at Stamford Bridge is normally a positive result," Mourinho added to Sky Sports. "To stay top of the league with that result is also a positive thing. But the dressing room is not happy, and that for me is fantastic. It is a complete change of mentality, a complete change of personality."
Mourinho needed time to instil that personality in his squad and he needed new signings too. Sergio Reguilon has brought fresh impetus at left-back. Gareth Bale and Carlos Vinicius have added impressive depth in attack. And then there is Pierre-Emile Hojbjerg in midfield.
The former Southampton captain has not received as many plaudits as many of his team-mates in the opening months of the season but he has been outstanding so far and, like Reguilon, he is a combative, determined individual whose character mirrors Mourinho's.
Hojbjerg has brought composure to the midfield as well as bite. The 25-year-old, who has not missed a minute for Spurs in the Premier League this season, completed every one of his 33 passes in the first half at Stamford Bridge on Sunday, helping to ensure Spurs did not lose control of the game.
Hojbjerg's combination of guts and guile is precisely what Mourinho needed in that area of the pitch but what's just as important is that the Spurs boss is getting more from players who were already at his disposal.
Kane, always a prolific scorer, is now the Premier League's leading creator too, a vital link between the midfield and attack who has contributed nine assists in 10 games, while Tanguy Ndombele's transformation has been even more impressive.
The Frenchman's future looked in jeopardy as he struggled to win over Mourinho last season, but his performance against Chelsea provided further evidence that he is now delivering on the potential that convinced Spurs to part with a club-record fee to sign him from Lyon last summer.
In the first half, he had Gary Neville marvelling at his quick feet to elude two Chelsea players. "[N'Golo] Kante and [Thiago] Silva are no mugs, but he skips through them," said the Sky Sports pundit. In total, he made twice as many dribbles as any of his team-mates and won the most fouls too.
Even more significant, however, was that, at the time of his substitution in the second half, Ndombele, a player previously criticised by Mourinho for a lack of work-rate, had covered more ground (8.2km) and registered a higher average speed (7.52 km/h) than any other Spurs player.
Ndombele's output underlines the way in which Mourinho's methods have taken hold at Spurs and while a goalless draw is not a result to be celebrated - "That's the thing that makes me really happy, that we are not happy," added Mourinho afterwards - it does at least show that Spurs are moving to their manager's tune. No wonder he's smiling.