Manchester City boss Manuel Pellegrini has revealed that striker Sergio Aguero faces a race against time to be fit for the first leg clash with Barcelona in the last-16 stage of the Champions League in February.

The Argentine, who has hit 19 goals in all competitions for the Sky Blues this season, was ruled out for a month after sustaining a calf injury in the 6-3 demolition of Arsenal at the weekend.

However, speaking to reporters following his side's 1-3 win over Leicester City in the quarter final of the Capital One Cup this evening, Pellegrini said that the hitman could be facing an eight-week layoff, placing his inclusion for the visit of the Spanish giants on February 16 in doubt.

"I am not a doctor. It is very difficult. The doctor has said he has at least one month or eight weeks. We will see," said the Chilean.

"I don't how many weeks but it will be at least one month. It is very difficult to know at this moment how many weeks it can be."

Lionel Messi, who is also sidelined through injury, is expected to return to fitness in time for the trip to Manchester.