Tottenham Hotspur have a defence.
Not since Harry Redknapp's final season at the club have Spurs had a solid central defensive pairing upon which they could build.
Then, in 2011-12, Spurs conceded just 41 goals (eight fewer than Arsenal) with a fully fit Younes Kaboul and a struggling but still often excellent Ledley King at the heart.
Last season, Michael Dawson was the mainstay, making 31 appearances in the Premier League as Spurs saw 10 more opposition goals than two seasons earlier.
Dawson generally played alongside one of Kaboul, wrecked by injuries and a shadow of his former self, Vlad Chiriches or Jan Vertonghen.
Dawson's obvious flaws as a defender had led Andre Villas-Boas to attempt to sell him during the summer, but he chose to remain at the club and fight for his place. He succeeded in forcing his way back into the team, but Spurs were regularly torn apart by the better sides.
The previous season featured the same rotating group with Steven Caulker in place of Chiriches.
At no point since Redknapp's departure have Spurs been able to rely upon a consistent defensive partnership. Few things in football are predictable, but it is a certainty that a central defensive partnership improves with time.
Through injury, suspension and lack of form, Villas-Boas and his successor Tim Sherwood were unable to find a pair that they could stick with.
Mauricio Pochettino had been suffering from the same fate in his early months at Spurs.
Chiriches lost his place after a series of erratic performances while Kaboul has been unable to recover his best form after losing the better part of two years to injury.
When Spurs signed Sevilla defender Federico Fazio in the summer, it seemed obvious that he and Vertonghen could eventually form a solid partnership. Fazio is excellent in the air while Vertonghen deals well with the ball on the ground. The Argentinian is huge while his Belgian counterpart moves smoothly.
Argentinian football expert Dan Edwards described Fazio's qualities as "much more than just a threat in the air. He possesses excellent anticipation and timing, breaking down opposing attacks on the floor before forwards have a chance even to touch the ball."
Edwards is perhaps euphemistically describing Fazio's worrying habit of charging out of defence to intercept a pass. When it works, this a source of momentum and entertains the crowd, but it has the potential to cost him if he miscalculates his timing.
Vertonghen enjoyed an excellent first season in England. Joining from Ajax, he quickly became vital to Spurs' success and was eventually named to the PFA team of the year. Last season, the team regressed, and he struggled to reach the heights of his debut season.
Now, though, with Fazio and Vertonghen established as the first-choice defence pairing, both are growing in confidence.
The pair have been selected in each of the last five Premier League matches as well as the League Cup win against Newcastle United. In that time, Spurs have been beaten only once—against Chelsea. While the pair have only managed two clean sheets from those six matches, it is clear that they are developing a partnership.
Against Crystal Palace and Newcastle particularly, any viewer could see the communication between the two. They were stretched by Swansea City, and Wilfried Bony in particular, but in an odd kind of match, they did enough for Spurs to claim the win.
Pochettino has also found the full-backs necessary for his demanding system. Players like Danny Rose and Kyle Naughton are adequate substitutes, but now that Kyle Walker and Ben Davies are established at right- and left-back, respectively, Spurs have a dependable and effective back line.
Weaknesses remain as this back four have only played one match together. The goal conceded against Swansea came from a breakdown of understanding as Davies clearly thought Vertonghen would come across in cover.
Walker and Davies are both strong defenders that can contribute in attack. Davies lacks Walker's insatiable drive and pace, but his sense of timing is excellent, and it often sees him arriving precisely when he is needed.
It will surprise no one that Pochettino's first-choice defence is Walker-Fazio-Vertonghen-Davies. They are his four strongest defenders.
The fact that they are all fit and playing together means that Spurs approach a busy and potentially decisive month with a solidity that has been lacking for more than two years.
Pochettino can commit greater numbers in attack knowing that he no longer has liabilities lurking in his back line.
They are not an excellent defence yet, only time can prove that, but they have all of the necessary components. There is an understanding, particularly between the central pair, but that needs experience in order to grow.
Chelsea's visit to White Hart Lane will be particularly instructive. Their 3-0 triumph in the reverse fixture could have been much more as the Blues pulled back once they had established a decisive advantage. Equally, though, each of their goals came from defensive errors.
When they arrive on New Year's Day, it will reveal just how far the defence has come.