The injury to Romeu causes a problem for Chelsea at the defensive midfield position as they will only have Ramires to play the position once the month of January begins.
John Obi Mikel, who usually starts alongside Ramires at the position, will be leaving the club to compete for Nigeria in the African Cup of Nations.
With just one healthy player at the position going into January, manager Rafa Benitez will be forced to focus on bringing in a defensive midfielder during the January transfer window or find a capable internal replacement.
If Benitez chooses to find a replacement for Romeu and Mikel in the transfer market, he will have plenty of players to go after.
One potential player that the Blues could go after is a player that they have been linked to in the past week, Marco Verratti of PSG.
Verratti has started in 10 Ligue 1 matches this season for the Parisian club and he is a potential star in the making at just 20 years old.
If the Blues do not decide to chase the signature of Verratti, they could turn to two other stars of Ligue 1 to fill the void in the defensive midfield.
Those two players would be Etienne Capoue of Toulouse and Yann M'Vila of Rennes.
The better option of the two players at the moment would be Capoue, who has been the best player on the pitch for Toulouse all season.
Not only is Capoue a defensive force in the Toulouse 4-1-4-1 formation, but the 24-year-old can also score goals, something that Mikel has not done in his seven seasons at the club.
Capoue has three goals and two assists to compliment his defensive record this season for the ninth place club in the French top flight.
M'Vila plays in the same 4-2-3-1 formation at Rennes that Chelsea uses but the 22-year-old is currently out injured.
M'Vila is out until January and would not be a good buy for Chelsea during transfer window because they need someone who can come in and play at the position immediately with no recent injury concerns.
One final option that Benitez could consider is to fix the problem with players that he already has on the roster.
The two players that would be the best fit to replace Mikel and Romeu would be Frank Lampard and Oscar.
Lampard has been employed at the position in the past under former manager Roberto di Matteo and he would provide a veteran presence on the pitch.
Lampard does have to prove that he has his recovery from his recent calf injury to be a candidate for the starting spot at defensive midfield.
The 34-year-old did play 11 minutes against Sunderland on Saturday, an appearance that marked his on-pitch return to the Blues after being out for six weeks.
If Lampard is not fit, Benitez could move Oscar from his role in the center of the attacking trio in midfield to a partnership with fellow Brazilian, Ramires, in the defensive part of midfield.
Behind Lampard, Oscar is the only other true central midfielder on the Chelsea roster.
If Oscar were to be moved into the defensive midfield, Benitez would be forced to switch around the players in the attacking positions, where he has plenty of depth.
With Oscar shifted back into a more defensive role, Marko Marin or Victor Moses could be given an opportunity to more playing time alongside Juan Mata and Eden Hazard in the attacking midfield trio behind forward Fernando Torres.
Benitez has plenty of options to choose from as he tries to solve the crisis in the defensive midfield when January begins.
Whether he solves the crisis through a transfer or an internal move is for him to figure out and for Chelsea fans to criticize once the move is made.
All statistics provided by WhoScored.com
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