Over the duration of the extended summer transfer window, Tottenham Hotspur were linked with several central defenders, ranging from Inter Milan's Milan Skriniar to Beijing Guoan's Kim Min-jae.They eventually settled on an £11m move for Swansea City colossus Joe Rodon, who made his second-ever league start for Spurs in the win over Sheffield United on Sunday afternoon.However, the north London outfit continue to be mooted with potential defensive reinforcements this January as it's thought that Jose Mourinho still wants a "pacey centre-back," according to the Sunday Times' Duncan Castles.Well, they may well have missed out on a perfect option in Ruben Dias...

What was the word?

According to the ever-reliable Alasdair Gold at football.london back in September, Mourinho was a 'big fan' of the Portuguese international and monitored his ongoing situation at Benfica.

Though his release clause was thought to be the major stumbling block for Daniel Levy and co.

The Evening Standard's Dan Kilpatrick claimed similar too, suggesting that the 23-year-old was the 'preferred option' for the Special One in the summer.

Later that month, Dias signed for Premier League rivals Manchester City in a £65m deal which saw Nicolas Otamendi sent in the other direction, as per Sky Sports.

He's since gone onto transform Pep Guardiola's struggling defence tenfold.

One that got away?

The Manchester Evening News revealed last month that Dias has already 'stood out' with his leadership qualities at the Etihad Stadium.

Indeed, he has made his presence known since his arrival - per WhoScored, he's started as many games as Kevin De Bruyne and tops the charts for clearances per game (3.1).

Before his introduction against Leeds, City had conceded seven goals in three matches, but in his 15 starts since, they've kept nine clean sheets and have only leaked five goals.

That is an incredible impact, to say the least. Perhaps it's an understatement too.

It's no wonder City are firmly back in title contention, sitting in second place, whilst Spurs have faltered down to fourth despite holding the top spot just a few months ago.

Overall, he's been a far better player for City than Davinson Sanchez, who has been linked with an exit from north London this window, has been for Spurs.

Dias has managed a better average rating of 6.91 compared to a disappointing 6.48 as per WhoScored.

He's also been less wasteful in possession, completing an impressive average of 93.4% of his passes compared to Sanchez's 84.7%, whilst the City sensation has even managed more interceptions (0.9) and blocks (0.9), as well as fewer fouls (0.5), and is rarely dribbled past (0.1 times) per game.

On the other hand, Sanchez has been rather suspect, being dribbled past five times as much and he also commits over double the number of fouls as Dias, proving to be Mourinho's biggest bugbear in defence.

That much has been evident too as since West Ham's shocking comeback in October, the Colombian has been completely snubbed in ten of 13 matches, per Transfermarkt.

If only Mourinho was able to sign his fellow countryman...

Praise of the £54m-rated colossus only adds further misery to this failed swoop, Guardiola told reporters, via talkSPORT: "I can assure you that we signed one incredible player for the next five, six, seven years." That is not easy to find, whilst ex-Saints man Jose Fonte has already dubbed him a "leader."

If the Spurs boss was truly chasing Dias in the summer, then he may well never live down Levy's failure to clinch him. As seen above, he's been one of the classiest and best defenders in the top-flight this term.

It's one massive Sanchez upgrade missed.

AND in other news, Forget Lingard: Mourinho has to unleash teen prodigy with a "HUGE future"...