Premier League leaders Liverpool and champions Manchester City are heading into an intense month of fixtures with neither looking close to their best.
Liverpool laboured to a 1-1 draw with Napoli in the Champions League on Wednesday, lacking the intensity and attacking potency that has been at the heart of their success under manager Juergen Klopp.
City stumbled to a 1-1 draw with Shakhtar Donetsk in the same competition, with no sign of the zip and verve that has characterised Pep Guardiola's team over the past two title-winning seasons.
Both looked like sides who could do with a rest, a nice week in a warm-weather resort recharging their batteries, but the price of competing at the highest level -- at home and abroad -- is a gruelling December that offers no respite and plenty of potential bumps in the road.
City need no reminders of the dangers that lie in wait for them in Newcastle on Saturday -- one of their four defeats last season came in a 2-1 reverse at St James' Park in January.
With their all-time top scorer Sergio Aguero sidelined by injury, Guardiola is banking on his only other striker, Gabriel Jesus, delivering goals and keeping fit through the coming month.
He also needs his team to rediscover the slick passing game and dominance of midfield that has been their hallmark but has been sorely missing in recent weeks.
Injuries are part of the process at this time of year especially and Liverpool suffered a blow with their key holding midfielder Fabinho picking up an ankle injury against Napoli.
It is unclear how long the Brazilian will be sidelined for but they will probably be without him at home to Brighton on Saturday.
Against Napoli, only Roberto Firmino looked in top form and that will be a concern for Klopp as he heads into a month in which his team also have to contend with two games in Qatar in the Club World Cup.
To add to the workload, both teams have derby matches on the horizon with Liverpool hosting Everton on Wednesday and City taking on Manchester United on Dec. 7.
It looks the ideal moment for second-placed Leicester City to take advantage and push themselves into the race.
Brendan Rodgers' side are a point ahead of City and eight behind Liverpool and on Sunday they face an Everton team whose manager Marco Silva will be worrying he might not even survive to Wednesday's Merseyside derby.
Another manager under intense pressure is West Ham's Manuel Pellegrini who won't be looking forward to Saturday's visit to in-form fourth-placed Chelsea.
Manchester United host Aston Villa at Old Trafford on Sunday with Ole Gunnar Solskjaer's side in need of a convincing performance after struggling for large parts of their 3-3 draw at Sheffield United.
Jose Mourinho will look to make it three wins out of three since taking over at Tottenham Hotspur when Bournemouth visit North London on Saturday.
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