An obvious area of weakness for Arsenal in recent weeks has been in the full-back positions. With Andre Santos, Kieran Gibbs, Bacary Sagna and Carl Jenkinson all out injured, Arsene Wenger has been forced to play centre-backs out of position there. And, after Johan Djourou was sent off against Fulham when looking thoroughly uncomfortable at right-back, away at Swansea Ignasi Miquel struggled in an unfamiliar left-back role. Those two look likely to start again in Sunday's home fixture with Manchester United.
The Premier League champions will surely look to target that area and exploit Arsenal's vulnerability there, particularly at left-back. Sir Alex Ferguson has an interesting choice for the right of midfield - Nani terrorised Arsenal in this fixture two years ago from the right, which turned out to be the start of an impressive run of form.
But Antonio Valencia enjoyed an excellent game against Bolton last weekend and might be more of a natural wide right player to take on Miquel down the outside and get crosses in. The contrast in NaniÃ¢ÂÂs and ValenciaÃ¢ÂÂs play is shown below: NaniÃ¢ÂÂs performance against Arsenal earlier in the season, and ValenciaÃ¢ÂÂs from last weekend.
The first meeting between Chelsea and Norwich this season was an interesting tactical battle. Paul Lambert played a 5-3-2 away at Stamford Bridge, which meant Norwich had cover at the back, but left the Chelsea full-backs free Ã¢ÂÂ that turned out to be crucial, as Jose Bosingwa moved forward unmarked to thump in a brilliant opener.
But at the other end of the pitch, Norwich caused Chelsea significant problems by knocking the ball over the defence and getting Grant Holt to challenge John Terry and Branislav Ivanovic in the air, with ten free-kicks resulting from these challenges.
NorwichÃ¢ÂÂs aerial route is crucial to their game Ã¢ÂÂ theyÃ¢ÂÂve scored more headers than any other side this season, and it will be interesting to see if Andre Villas-Boas gives a debut to Gary Cahill alongside Terry at the back, or retains Ivanovic, who is probably better in the air despite his previous struggles against Holt.
Either way, it will be a physical contest Ã¢ÂÂ and the diagrams show that Holt prefers to battle against the right-sided centre-back, rather than Terry, who plays to the left.
Tottenham striker Emmanuel Adebayor is on loan from Manchester City and therefore unable to compete against his parent club, which will probably mean a start for Jermain Defoe as the lone striker on Sunday, with Rafael van der Vaart just behind him.
This isn't a game that will naturally suit Defoe's qualities - away from home Harry Redknapp would probably prefer a strong striker who can hold the ball up, but he doesn't seem to have much faith in Roman Pavlyuchenko, Adebayor's natural deputy.
Defoe has evolved his game to become a better all-rounder in recent years, however, and his link-up play is much better than a couple of seasons ago. He should look to come deep and drag centre-backs away from their natural position - Stefan Savic, in particular, lacks inexperience and can be pulled around. DefoeÃ¢ÂÂs passing from last start, against West Brom, shows how deep he often drops.
Landon Donovan's return to Everton for a two-month loan spell has reaped instant rewards - his excellent through ball to Victor Anichebe rescued a point last week at Villa Park,It's exactly the sort of thing Everton have been missing. This season, they average only one through ball per match, a terrible record equal with the likes of Stoke and Norwich, sides that unashamedly play long balls and hit crosses towards big central strikers. It shows that, in addition to lacking a regular goalscorer, Everton also miss creativity from midfield positions to set up chances in the first place.
Donovan provides that Ã¢ÂÂ against Aston Villa he played more passes in the final third than any other player, and also created the most chances, three. This weekend heÃ¢ÂÂs up against Blackburn, who concede over two goals per game, meaning the American is likely to play a key role.