Man City's next three matches -- Man Utd., Swansea, Spurs -- will either decide title race or open it back up

Despite the calendar reading December, there are just seven days to save the title race. A single week will either slow Manchester City down or turn the Premier League into a procession. The most important period of the season is about to begin.

Pep Guardiola's team faces a three-game stretch that contains two potentially epic matches. They start at Old Trafford for a derby with a host of subplots.

Manchester United are not used to being second-best in town. They are eight points behind their neighbours and cannot afford to slip further adrift. The bad blood between Jose Mourinho and his Catalan rival goes a long way back. It has always been a clash of footballing cultures when these managers meet and the Portuguese's resentment toward Guardiola is palpable.

City are unbeaten in the league and have only drawn once. At times during the campaign they have played in a spellbinding manner. Their recent form has not been quite as sparkling, but late-goal victories against Huddersfield Town, Southampton and West Ham United have shown another side to their character: the ability to grind out victories against opposition bent on defending deep and killing the game. The knack of grabbing last-gasp victories is the hallmark of champions.

For Mourinho, those games show that City can be stopped. The United manager would have to be exceptionally brave -- or foolhardy -- to set his side up in an extremely negative manner for the derby. There has already been criticism about the 54-year-old's tendency to resort toward conservative and defensive methods. Old Trafford expects a certain amount of flair from the Red Devils. If Mourinho parks the bus and is then beaten, the fury will stretch from the Stretford End to the boardroom.

United are a big, powerful side. They have pace up front and a physical midfield. They are strong in the areas in which City are weakest. Their performance in last weekend's 3-1 victory over Arsenal showed just what they can do. At the Emirates, United sat deep but broke at speed. The plan was to get the ball to Paul Pogba for the Frenchman to advance at pace, with Anthony Martial and Romelu Lukaku surging ahead. They caused havoc for the home side's defence.

Mourinho took advantage of Arsenal's tendency to overcommit the midfield. City barely have a midfield. Fernandinho polices the area in front of the defence, but the greatest strength of Guardiola's team is the front five. They press defenders hard and do much of their ball-winning in the attacking third of the field. Sides that try to play out from the back against City suffer.

To be successful in the derby, United need to get the ball forward quickly. Without Pogba -- suspended for his dangerous tackle on Hector Bellerin -- Mourinho's midfield does not have the same thrust.

It is likely that Mourinho will use Marouane Fellaini in a similar manner to the Europa League final against Ajax in May. United knocked the ball long to the Belgian to avoid the press. The hope is that Fellaini's physical approach will trouble the City defence.

After their trip to Old Trafford, Guardiola takes his men to South Wales to play Swansea City three days later. Paul Clement's team go into the weekend stranded at the bottom of the table and do not look equipped to worry City. What they can do is take heart from the way fellow bottom-half teams have frustrated the leaders until the late stages of games over the past month. Clement's ideal scenario may be that City emerge from a bruising derby with key injuries.

The final act of the week-long saga is at the Etihad, where City host a stumbling Tottenham Hotspur team. Mauricio Pochettino's side entered the season believing that they were the main threat to City. That has not been the case so far as they have been hampered by injuries and a crisis of confidence as opponents have worked out how to nullify their strengths.

Part of City's success this season has been the way the wing-backs have performed. Kyle Walker and Fabian Delph have functioned above expectations and are expected to supplement the midfield when their team is under pressure in the middle of the park.

Walker cost City £50 million from Tottenham in the summer and many believed that the London club got the better end of the deal. It has not proved that way to this point.

Pochettino's team get their width from wing-backs. Walker and Danny Rose were an important part of the side's development. With Rose out of favour, Spurs have struggled to generate any threat from their wing-backs.

Teams have developed methods to stop Tottenham. They sit deep and crowd the areas where Harry Kane likes to operate. Pochettino's midfielders are talented and are unlikely to be outrun by opponents, but they struggle to unlock tight, compact defences. They match up well against City, though.

Guardiola will not be concerned with stopping Spurs. City will play their normal game. This means Tottenham will have a chance to dominate the midfield and determine the pace of the game. City's defence has flaws and Kane has the potential to cause chaos within the home team's back line.

Tottenham cannot afford defeat. They are already 18 points behind City and are now engaged in a battle for the Champions League places. Their run of form has left them with little margin for error.

Given City's lead at the top, they can afford a draw or two. To keep the season alive, however, United and Tottenham -- and perhaps Swansea -- need victories. This seven-day run will be an examination of City's mettle. It will be even more testing for the three teams trying to stop them from running away with the title.