City’s request to delay Yaya and brother Kolo's departure for the Africa Cup of Nations until after Sunday’s tie at the Etihad Stadium was rejected by Ivory Coast on Thursday.
And Summerbee, now working as an after dinner speaker, says the Blues were always aware of the tournament so must adapt to the situation.
“When you see him he looks sluggish, but when he gets the ball he has that acceleration. They’ll both be missed, but it’s like with Newcastle United and their two players [Demba Ba and Cheick Tiote]. City knew this would happen and have to cut their cloth accordingly,” he told FourFourTwo.com
Manager Roberto Mancini has used the League Cup to give fringe players a chance this season, but Summerbee feels that will not be the case in the FA Cup on Sunday.
“They want to start building the trophy cabinet so they’ll put out a strong team,” he said, “In a Manchester derby you can’t afford it, you have to go full strength. I think Manchester United will do the same thing.”
Despite beginning his career at Swindon Town, Summerbee played more than 100 times for the Citizens, and has tipped his former club to progress to the next round saying:
“Manchester United have been dominant for a lot of years and now City have a chance to step up. I think City will be looking forward to this game.
"Normally form goes out the window with derby games, but Man City are in good form and scoring goals without always playing well.
"Having that is great. The players they have now are world class players. They’re a big strong team so they’re hard to break down.”
