Manchester City's defence with Vincent Kompany is probably good enough to win the Premier League - but without him it may not be.
Kompany's absence with injury is a massive worry for City because his replacements are nowhere near his standard.
They need him back soon, even though their strikers are doing the business at the other end of the pitch, at the Etihad Stadium at least.
City look a lot stronger with Kompany at the heart of the back four and I think his presence helps Matija Nastasic, who impressed me with his performances last season and is the man I think should regularly partner the Belgian.
Nastasic hasn't had the greatest start to the season but he is still young and will make mistakes because that's the nature of the centre-back position, somewhere where you improve with experience.
I thought he showed a fantastic temperament when City played Real Madrid at the Bernabeu in one of his early games last year and he always strikes me as very cool and calm under pressure and not someone who will panic.
I am a little bit surprised that Joleon Lescott has not figured more, though, because City won the title with him alongside Kompany a few seasons ago.
Lescott is also vastly experienced at Premier League level and extremely powerful, something you often need in tough away games, an area where City have had issues this year.
Some people might question Lescott's pace and while you'd rather be quick than not, I still think reading the game is more important.
John Terry is not blessed with express pace but is still one of the top English centre-backs in the country.
Micah Richards is blessed with pace, strength and athleticism so you'd think he might be ideally suited to centre-back, but he hasn't really played there enough times for us to say that that is his best position.
I remember watching him in youth teams and when he first burst onto the first-team scene and, for someone who does not look the tallest, he had an unbelievable spring and was very decent in the air.
But he has played much of his career at right-back and now that he is behind Pablo Zabaleta in the pecking order, it is getting to the stage where he is going to have to either make that position his own or move on and become first choice somewhere else.
I also think Gael Clichy will eventually become City's first choice left-back.
Manuel Pellegrini has been alternating him and Aleksandar Kolarov but I think the Frenchman will get the nod more often because he is a slightly better defender - if not in great form at the minute.
You'd imagine City will get more solid the more Yaya Toure and Fernandinho play together in central midfield, too - though I think they have done okay as it is, especially in the Manchester derby when they dominated the midfield.
But the key thing for Pellegrini is to get Kompany fit and Joe Hart back in form and in goal.
Tottenham, meanwhile, are struggling a little for goals and I think much of that is down to them having to gel a lot of new players into the team; Paulinho has done really well but some of the others are yet to settle down and find their places.
Christian Eriksen, when fit, is the sort of technical player that should be able to unlock a defence; he is different to Spurs' big, powerful players and could spark them into life with that final pass, something they may have been lacking.
But I also think Erik Lamela is a candidate to play in that No. 10 position.
He is predominantly a wide-right man but with the emergence of Andros Townsend and the fact he had a decent goals-to-game ratio at Roma suggests maybe they could use him off the striker.
Getting Moussa Dembele into games could be crucial, too, because he has got the lot as a midfield player - pace, strength, mobility and quality on the ball - but I think he needs to add more goals and assists to his game and really affect things at the top end of the pitch.
Tottenham have been very solid at the back, though - the game against West Ham aside - but they will face probably the best attack in the Premier League on Sunday so it could be a very difficult afternoon for them.
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