The Ivory Coast international was replaced by Javi Garcia after 16 minutes of City’s 3-2 loss to Liverpool at Anfield on Sunday.
Maybe it’s not so bad as we thought at the beginning but he needs at least ten days or two weeks to recover
Toure has been a key figure in the Citizens’s title challenge this season, scoring 18 goals and making five assists in 31 Premier League appearances.
And Pellegrini confirmed that Toure is set to miss City’s home games against Sunderland and West Bromwich Albion this week.
“Yaya has a muscle injury – we’ll see with the doctor how many days,” Pellegrini told his pre-match media conference.
“Maybe it’s not so bad as we thought at the beginning but he needs at least ten days or two weeks to recover.”
However, Pellegrini did have good news for City supporters, revealing that Vincent Kompany and Sergio Aguero are in line to start against the Baggies.
“Vincent is on the squad list for tomorrow, so is Sergio – we’ll see who starts,” Pellegrini added.
Third-placed City are seven points behind Premier League leaders Liverpool after their loss at Anfield on Sunday.
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