Manchester City manager Manuel Pellegrini says his players will not underestimate West Ham United.
Sam Allardyce's side broke into the top four after wins against Queens Park Rangers and Burnley and the Chilean knows his players have to be focused if they are to take all three points from The Boleyn Ground.
"Every Premier League game is difficult," Pellegrini told reporters.
"West Ham are in a very good moment, playing attractive football so we know we will have a tough game as always.
"They have different players and are playing in a different way to last season. They brought in two important strikers who are doing well.
"They had an important win against Liverpool at home and have won their last two games so I am sure we will have a difficult rival.
"Frank [Lampard] is not ready for this week but maybe next week he will start working with the whole squad.
"After we got back from Russia Nasri was working with whole squad and maybe next week he will be ok. All the other players in the squad are fit."