Cesc Fabregas is struggling to be fit for Chelsea's Premier League games against Aston Villa and Everton, which could open the door for the club's new signing Juan Cuadrado to make his debut.
Already without the suspended striker Diego Costa for the next two games, manager Jose Mourinho fears that -Fabregas may not fully recover from a hamstring injury in time to face Villa or Everton.
The midfielder sat out the Premier League draw with Manchester City last weekend after injuring his hamstring against Liverpool in the Capital One Cup semi-final second leg.
Costa and Fabregas have been Chelsea's best players this season and missing both would be a big blow for Mourinho, even though relegation-threatened Villa should provide straightforward opposition.
Chelsea travel to Villa on Saturday before hosting Everton four days later and Mourinho will not want to take any risks on the fitness of Fabregas with the first leg of the Champions League tie against Paris St-Germain on Feb 17.
Ramires stepped in for Fabregas against City. He will be favourite to keep his place if Fabregas cannot play against Villa or Everton. But Ramires has only just returned to full fitness after struggling with injury, which could prompt Mourinho into handing a starting place to winger Cuadrado against either Villa or Everton.
Mourinho has the option of playing Oscar in a deeper role next to Nemanja Matic to free up a place in the front three for Cuadrado, or resting Oscar, Eden Hazard or Willian.
Having appeared in Europe only in the Europa League for his former club, Fiorentina, this season, Cuadrado has been included on both of Chelsea's Premier League and Champions League squad lists after joining in a pounds 23.3?million deal that will rise to pounds 26.8?million.
Cuadrado has replaced Andre Schurrle, who yesterday insisted he had no regrets about his Chelsea career after joining Wolfsburg.
Schurrle initially wanted to stay at Chelsea until the summer, but a lack of first-team opportunities convinced him the time was right to leave.
"I wanted to stay but, the last weeks or last month, I tended towards changing something because I wanted to do what is fun for me and that is to play football," the World Cup winner said.
"I could only do it briefly at Chelsea in the past weeks. I will never regret Chelsea. I still love this club, the staff are amazing. I developed my game, I improved myself there. I was a different player when I came to Chelsea. It helped me a lot."
Wolfsburg paid Chelsea a pounds 24.1?million fee for Schurrle, with an extra pounds 3.7?million potentially due in add-ons. Sporting director Klaus Allofs said: "The financial aspect has been made into an issue, but an engagement of this size makes sense. I don't think we are breaking the bank if you look what is happening around Europe."