Wanchope has asked national coach, Steve Sampson, to be disregarded for his country's friendly fixture with South Africa on 11 October so that he doesn't risk his fitness and can fight to keep his place.
Keegan was expected to restore the former Anfield partnership of McManaman-Fowler but surprisingly opted for the Costa Rican after he scored in last Tuesday's reserves win.
"It wouldn't be fair just now when I am getting totally recovered to play a friendly match," said Wanchope. "So I hope that the coach and the federation understand why I have asked not to be included in that match."
The signing from West Ham also stated his wish to repay the club, the manager and the fans for their loyalty after so long injured, and a potential move abroad in the summer.
"I heard some rumours, then a journalist phoned from Spain, so I went in to see the boss and he told me there had been an offer,” Wanchope told BBC GMR.
“He said he wanted me to stay but it was my decision. I didn’t want to go because I feel I owe something to the club and its supporters.
“I haven’t played for almost two years, yet people still want me. That was so nice to here because I am really happy at City and I want to give something back.”