Manchester City manager Pep Guardiola.

With Manchester City on a record-breaking sprint towards the Premier League title, the leaders have reached the halfway point of the season looking simply unstoppable.

The future is bright for Pep Guardiola's side, but City's rivals face a more uncertain time in 2018 as they try to bridge the gulf in class.

With 19 games played in the 38-match campaign, AFP Sport compiles a half-term report for the Premier League's big six ahead of the Boxing Day fixtures.

Manchester City

When City's Abu Dhabi-based owners hired Guardiola last year, they dreamed of the Spaniard delivering bountiful success in swaggering style.

A trophy-less first season in England was a huge disappointment, but the former Barcelona and Bayern Munich boss has worked his magic this term.

Playing such dazzling football that they have already been ranked among England's all-time great teams, City have reeled off a record 17 successive league wins to move 13 points clear at the top.

Guardiola spent big money to overhaul his squad in the close-season, but he has also shown a deft touch to bring the best out of key players like Raheem Sterling and Kevin De Bruyne.

The title race has been turned into a lengthy coronation by unbeaten City and, ahead of their visit to Newcastle United on Wednesday, the only questions remaining are how early they clinch the trophy and how many records they set in the process.

Manchester United

When Romelu Lukaku sprinted clear to notch his first league goal for United on the opening weekend of the season against West Ham United, it seemed Jose Mourinho had found the powerful attacking talisman that all his best teams have employed.

Lukaku, a close-season signing from Everton, hit 11 goals in his first 10 games as United matched free-scoring City blow for blow, but suddenly the goals dried up for the Belgian.

With Lukaku under fire from his own fans, the increasingly tetchy Mourinho has been unable to scheme enough goals from other areas.

The nadir coming in a tedious 0-0 draw at Liverpool when Mourinho's cautious tactics were widely panned.

City's 2-1 win at Old Trafford was another hammer blow and United, who host Burnley on Tuesday, may need more major investment to catch up.

Chelsea

The champions hadn't even started their title defence when Blues boss Antonio Conte gave an ominous warning about their prospects.

Frustrated by Chelsea's failure to land his top transfer targets, Conte was already convinced his squad lacked the depth to compete for the title and challenge in the Champions League.

The Italian has been spot on and City showed how far ahead they were with a clinical 1-0 win at Stamford Bridge, while dismal losses at Crystal Palace and West Ham have kept Chelsea from establishing any momentum.

Alvaro Morata's predatory finishing in his debut season has been one of the few bright spots for Conte, whose side take on Brighton and Hove Albion on Tuesday languishing 16 points behind City.

Liverpool

Last Friday's scintillating 3-3 draw at Arsenal showcased everything good about Jurgen Klopp's commitment to an eye-catching style of play -- but just as significantly it emphasised the problems with the German's team as currently constructed.

Having taken a two-goal lead with some enterprising play from their 'fab four' of Philippe Coutinho, Mohamed Salah, Roberto Firmino and Sadio Mane, Liverpool then collapsed at the back and conceded three goals in five minutes.

Sloppy defending and weak goalkeeping from Simon Mignolet have been a recurring motif of Klopp's reign and, with fourth-placed Liverpool hosting Swansea City on Tuesday, the problem must be resolved soon if the Reds are to avoid a season of underachievement.

Arsenal/Tottenham

Arsene Wenger has presided over the latest in a long line of underwhelming Arsenal campaigns and the Gunners go to Crystal Palace on Thursday an incredible 21 points behind City.

Wenger's failure to persuade Alexis Sanchez and Mesut Ozil to extend their soon-to-expire contracts has been a huge distraction and Arsenal's wait for a first title since 2004 is destined to go on.

Across north London, fifth-placed Tottenham Hotspur have been unable to build on last season's second-place finish as they struggled to adapt to playing their home games at Wembley while White Hart Lane is redeveloped.

Problems in away games against their top-six rivals have added to the angst for boss Mauricio Pochettino.

Fixtures (1500 GMT unless stated)

Tuesday

Bournemouth v West Ham, Chelsea v Brighton, Huddersfield v Stoke, Liverpool v Swansea (1730 GMT), Manchester United v Burnley, Tottenham v Southampton (1230 GMT), Watford v Leicester, West Brom v Everton

Wednesday

Newcastle v Manchester City (1945 GMT)

Thursday

Crystal Palace v Arsenal (2000 GMT)

Source: AFP