Twelve to fifteen points.

That’s what Petr Cech would be worth to us this season according to a man who would know (on this subject at least): John Terry.

Numerous people have attempted to tot up his contribution so far, but It’s hardly an exact science. Certainly our Czech stopper is already well on his way to having Terry’s prophesied impact as we sit pretty at the top of the Premier League and five points better off than the same fixtures last year.

Unfortunately, even he couldn’t prevent us from being ‘Mike Dean’d earlier on this season in the away fixture at Stamford Bridge back in September, but as Chelsea visit the Emirates this weekend he has a chance to make the difference and help us to secure the points against his former club.

Chelsea, for all their struggles, remain a tall side, with the likes of Costa and Matic matched by the towering defensive figures of Terry, Cahill/Zouma and Ivanovic. Cech’s height and aerial dominance will be critical in relieving the pressure on our defence at set pieces, where our goals conceded statistics are creeping upwards again following a strong start to the season.

Eight of Chelsea’s 31 goals this season so far have come from set pieces, admittedly including a number of Willian free kicks, but this set piece goal % of 26% is one of the highest in the league. We have scored eight set piece goals too, but at a lower % of our total goals of 22%. We will need Petr in top form to prevent Chelsea adding to that tally on Sunday.

Our totemic hero will have more reasons than most for wanting to deliver at the weekend. He may have remained remarkably muted and professional about the whole situation, but the circumstances of Cech’s departure from Stamford Bridge in the summer has left him with something to prove. Discarded for a younger and less experienced goalkeeper, he will no doubt want to demonstrate to the Chelsea hierarchy that they were wrong to lose faith in him, and that can only be a good thing for us.

Historically we have usually performed well against the so called lesser lights of the Premier League while falling down against some of the bigger boys, and our record against Chelsea is one of the worst of the lot. Having one of their greatest ever players in our dressing room will not only give them pause for thought, but it should give our players a lift too.

Hector Bellerin was quoted this week on the importance of knowing Cech is in situ behind the defence, and certainly there is a much greater aura of calm around our back four this season than in years gone by. Knowing that the man who has thwarted us on so many occasions in the past now resides between the sticks of our own goal should not only give us confidence but strike fear into the hearts of those Chelsea players who have trained with him for many years, as they know just how good he is.