It’s what the Premier League is supposed to be all about: two clubs with world class squads, world class managers and everything to play for at the top of the table.

They are probably the two teams most emblematic of the Premier League’s most recent flirtation with money. They are also emblematic of the way the Premier League has changed since the start of the season. New tactical ideas have replaced the old ones and breathed fresh life into a flagging league.

This season, the top teams really are the top teams, the top six is made up of exactly the clubs you would have expected to find there, just perhaps not in the right order. And whilst that might not sound like a good thing, the reality is that those top clubs have played some great football along the way: they’re top because they deserve to be, not just by default.

Antonio Conte and Pep Guardiola personify that change: new managers with new ideas, but most crucially, they have both taken on failing clubs and turned them around. Now they are both part of the same title race, and their meeting this weekend will go a long way to deciding who will come out on top. If it doesn’t directly affect the end of the season, then it will influence the form of two title contenders going into the crucial Christmas period - and that matters a great deal.

Here are FIVE key battles to decide the outcome of the game.

John Stones & Nicolas Otamendi vs. Diego Costa

Middlesbrough v Chelsea - Premier League

Manchester City haven’t been too impressive at the back this season. In fact, they’ve kept two clean sheets all season. Which means two things: they live dangerously and are vulnerable at the back; and they are a stunning attacking force.

Chelsea, however, aren’t a bad attacking force either. Antonio Conte’s side have actually chalked up exactly the same tally as City in the goals scored column, and boast the Premier League’s joint-top goalscorer (with City’s Sergio Aguero) in Diego Costa. Keeping Costa quiet and John Stones mistake-free could be crucial.

Fernandinho vs. Eden Hazard & Pedro

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When Manchester City are in control of the ball, their full backs usually bomb up the field - or infield - leaving John Stones and - probably - Nicolas Otamendi to man the defensive line themselves.

In order to reinforce their two-man backline, Fernandinho steps into the gap between the two central defenders to make a back three. It will be up to him to stop Chelsea from counter attacking with precision on Saturday afternoon. City, at home, will have plenty of possession, so expect Chelsea to try to make use of the pace and guile of their inside forwards on the break.

N’Golo Kante vs. David Silva and Kevin De Bruyne

Manchester City v Middlesbrough - Premier League

When City are on song, it’s usually because David Silva and Kevin de Bruyne are.

If David Silva and Kevin de Bruyne both start, City will surely be looking to overload N’Golo Kante in the defensive midfield role. If Kante can make sure that neither of City’s playmakers have much space, Chelsea can cut off a crucial supply route to Guardiola’s devastating attack.

City’s wingers vs. Chelsea’s wing backs

Raheem Sterling

Victor Moses and Marcos Alonso have been in sensational form ever since Antonio Conte moved to a back three and played with wing-backs. Both players have been able to run forward and support the attack, providing the side’s width and allowing both Pedro and Hazard to cut inside, where they can inflict huge amounts of damage.

In Raheem Sterling and Nolito, City have two players who are perfectly set up to hurt Chelsea’s back three, however. They naturally hug the touchlines, making runs from outside in: so either Chelsea’s full backs drop deep to help out their central defenders - meaning they don’t help their attack as much - or they allow City to exploit the space behind them - dragging centre backs out of position to cover.

Sergio Aguero vs. Chelsea’s back three

Aguero

That’s not the only problem for Chelsea’s defence, however. The question of how to deal with Sergio Aguero is a conundrum for every side who ever faces City. The Argentine striker is world class, and his form this season - ten goals in eleven Premier League games - has been sensational.

A lot will rest on whether City can use the wings to disrupt Chelsea’s central three, if they can, then there will be more space for Aguero in the box. Not that he needs very much, though.