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Key Areas That the Premier League's Top 6 Sides Must Strengthen in January

With each of the Premier League's top six in action on Saturday, the weekend's results saw the race for the race for the top four spots heat up ever more.

With Liverpool, Tottenham, Arsenal and Manchester United all winning, Chelsea's shock win over champions Manchester City saw the battle at the top of the table take an intriguing turn.

Liverpool leapfrogged City to cinch the top spot in what was the most telling change, whilst United took a step closer to the rest of the big six with a comfortable win over Fulham.

Meanwhile, wins for all three of the London contingent saw the race for the top four draw even closer, with Tottenham just two points clear of Chelsea and Arsenal.

With little to separate the Premier League's big hitters in the upper reaches of the table, here is a look into the areas that each side may look to strengthen in the January transfer window to find the edge over their rivals in the race for the top four.

1. Liverpool - Attack

Following a succession of heavy investment in the previous two transfer windows, Liverpool have one of the most complete squads in the Premier League, with impressive strength in depth in every position.

What Liverpool lack the most, however, is an out-and-out striker who guarantees Jurgen Klopp's side 20-30 goals per season. Mohamed Salah has assumed the role as the Reds' chief goal scorer, but the Egyptian is not a natural centre forward.

Last season's top scorer, Salah is more adept to cutting inside from the right wing. However, with Roberto Firmino turning more provider than goal-scorer this term, Salah has often been utilised through the middle. A natural, prolific goal scoring focal point in attack would complete Klopp's setup.

2. Manchester City - Midfield

With Kevin de Bruyne's injury robbing City of their talisman, and an over-reliance on Fernandinho as their only recognised defensive midfielder undercutting Pep Guardiola's squad depth, midfield has to be an area for reinforcement in January.

The concerns from City's end at Stamford Bridge on Saturday were clear as Brazilian enforcer Fernandinho appeared to pick up an injury in the first half, with a general awareness that the 33-year-old is the champions' only defence-minded man in the middle.

Ilkay Gundogan is a robust option, but the German is injury prone. City missed out on the signing of Jorginho during the summer, as the Italian opted for a move to Chelsea, and the Citizens' failure to secure a backup option has left them short on numbers in midfield.

3. Tottenham - Defence

With a strong variety and depth of options at their disposal in both midfield and attack, the one area which appears short on options for Mauricio Pochettino is in defence. With Toby Alderweireld's contract due to expire at the end of the season, his place in the team appears far from certain.

Fellow Belgian Jan Vertonghen is also struggling to produce his best form this term, having formed such a traditionally strong partnership in central defence with his compatriot in the past. Spurs no longer have that consistency at the back, and Pochettino must seek to rectify that in the new year.

Davinson Sanchez and Juan Foyth appear to be the future for Spurs in the centre of defence, though Sanchez's injury problems and Foyth's error-prone nature are yet to be eradicated from the South American duo. The signing of a ready-made leader in defence in January would be a huge boost for Tottenham.

4. Chelsea - Attack

One area in which Chelsea clearly came up short during their stunning victory over Manchester City on Saturday was in the central striking position. Maurizio Sarri opted to oust both of his recognised centre forwards from the side, reflecting the Blues' need for a new focal point in attack.

Olivier Giroud was named on the bench at Stamford Bridge whilst Alvaro Morata was excluded from the matchday squad altogether, as Sarri opted to field Eden Hazard as a 'false nine.' Though the Belgian did a decent job through the middle, he was unable to have his usual impact in an unfavoured position.

Chelsea's greatest sides in the Roman Abramovich era have been virtually defined in their successes by the presence of great centre forwards such as Didier Drogba and Diego Costa. The Blues lack any such focal point at present, and are unlikely to return to the summit of the table without a recognised goal scorer of that ilk.

5. Arsenal - Attack

Though Arsenal have suffered a significant loss of depth in their defensive ranks, following the season-ending injury for Rob Holding and the suspensions picked up by Shkodran Mustafi and Sokratis Papastathopoulos on Saturday, the return to fitness of Nacho Monreal and Laurent Koscielny have eased their issues at the back.

On the other hand, Danny Welbeck's long-term injury has left Arsenal with just Pierre-Emerick Aubameyang and Alexandre Lacazette as the Gunners' only senior striking options. Though Unai Emery has found a successful formula for balancing his use of the pair in the Premier League recently, the demands of Europa League and cup football will require more options.

Eddie Nketiah was named on the bench for Saturday's win over Huddersfield and, though the youngster is a bright talent, he is largely untested at the top level. Unai Emery is lacking the kind of experience, versatility and impact that Welbeck had previously offered in reserve, and the signing of another more seasoned attacker could be key to the Gunners' season.

6. Manchester United - Defence

Though the situation with Paul Pogba has left Jose Mourinho in something of a predicament in terms of midfield selection, United maintain a wealth of options at their disposal in the middle of the park. Saturday's 4-1 thrashing of Fulham also suggested that United do have enough firepower at their disposal when Mourinho structures his attack effectively.

However, the Red Devils look desperately short of the kind of leadership and resolve at the back that served them so well under Sir Alex Ferguson. That shortage is largely the result of Victor Lindelof, Chris Smalling and co failing to fill the void left by defensive stalwarts Nemanja Vidic and Rio Ferdinand.

With United leaking goals as a symptom of their poor start to the campaign under Mourinho, the Portuguese manager must ensure that an established defensive leader is recruited in January to reinforce the centre of defence - much in the way that Virgil van Dijk did for Liverpool last season.