Rio Ferdinand has said that Manchester United will be "licking their lips" at the prospect of facing Manchester City's Eliaquim Mangala and Martin Demichelis in the derby on Sunday.
Man City brought on the two defensive substitutes during the first half of their Champions League 0-0 draw against Dynamo Kiev at the Etihad on Tuesday night. They replaced Vincent Kompany and Nicolas Otamendi, the starting centre-backs, who both suffered calf and leg injuries early on.
Otamendi is hopeful that he will be fit for Sunday's derby, but Kompany is the club's major worry as the captain has had issues with it in the past and manager Pellegrini has said that he will be out of action for at least one month.
Former United captain Ferdinand told BT Sport: "They have got Manchester United at the weekend. The Man United players, I'm sure, will be licking their lips at the two centre-backs that came on."
When discussing Kompany's influence on the club, Ferdinand said: "The record that they have without him is very worrying, considering what's to come for the rest of the season. They're a much better, more confident outfit with him. His presence enables other players to play better."
Sitting in fourth-place on the table, City are currently four points clear of Man United but only two clear of West Ham with nine games remaining this season for all three teams.
Liverpool are a comfortable seven points below the leading four on the table, but with a game in hand they are still a very present threat.