Manchester City boss Roberto Mancini insists Patrick Vieira is ready to make a big impact for the club.
The 33-year-old French international is yet to play for City since making his move to Eastlands from Inter Milan last month.
Vieira is now being lined up for his debut at Hull City on Saturday and Mancini has backed the former Arsenal star to make an impact.
"I know Patrick wants to go to the World Cup and for this reason alone I feel he can be very important for us over the next three or four months," said Mancini.
"He is a big player, both on the pitch and in the mind.
"We lost two games recently, against Everton and Manchester United. They were both very different games and at Everton I felt we were tired.
"But Patrick is so experienced maybe we would not have lost those games if he had been in the team."
Meanwhile, Mancini has backed Kolo Toure to remain his captain after being appointed by predecessor Mark Hughes.
"I want my team to have many captains out on the pitch, but only one player can wear the captain's armband - and that is Kolo," said Mancini.
"He is a very important player for us and a very good leader so I am very happy for him to continue."