Having only arrived from Benfica at the end of September, the central defender has made a huge impact in his first few months at City and shone again in Saturday’s vital 1-0 win at Southampton.
Another shut-out at the St Mary’s Stadium made it seven clean sheets from our last eight games.
And Guardiola believes that Dias has been the defining factor in our defensive solidity which has helped move City up into seventh place in the Premier League table.
“Ruben has helped us a lot to be solid, and he has settled perfect with John (Stones)," the manager reflected.
“It’s incredible - that is how we can still be there. Knocking on the door of teams above us. We need it to be stable and maybe one day players will be fresh to score the goals.
“Ruben doesn’t make a single mistake and he is always focused.
“He is able to lead the line, the same with John. Our club bought an exceptional defender - especially for the personality.”
Dias' commanding presence, comfort on the ball and tactical awareness has already led some to compare him with City icon and fellow central defender Vincent Kompany.
Pressed on whether he saw similarities between Dias and our former Belgian figurehead, Guardiola insisted it was impossible to make such comparisons.
But the City boss did assert that he believed Dias would prove a pivotal figure for the Club looking to the long-term future.
“No, it takes time and Vincent is irreplaceable. He had ten years here and Vincent when I met him was 30, 31 - Ruben is 23,” Guardiola pointed out.
“But what is important when you buy a player is that you have a feeling they will be settled for the next years.
“And we are pretty sure Ruben will give us big moments.”
Addressing the media in the wake of the Southampton victory, the manager also reiterated he didn't expect City to look to strengthen our strikeforce in the January transfer window
“No, I don't think so because the economic situation around world is what it is,” the City boss added.
“All the clubs struggle - we are not an exception.”
“He trained Friday but didn’t feel good about his teeth, about contact there. So, he didn’t join us here,” the boss confirmed.
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