But Hart returned in the League Cup defeat by Spurs in midweek and manager Sven-Goran Eriksson confirmed later this week that the England U21 keeper will be his number one keeper for the forseeable future.
Sven admits the decision puts Isaksson's City future in doubt as the 27-year-old wants regular football up to the end of the season to secure his place as Sweden's first-choice keeper at Euro 2008.
"I have had talks with Andreas and obviously he's not very happy," said Sven. "I had to make a choice and for this moment I've made the choice in Joe Hart.
"I don't know if Andreas wants to leave or stay and fight for the place, but I told him it's very much up to him. I will not be surprised and I will understand it if he wants to leave.
"It was important and for the players to come up with this decision before the transfer window opens in January."
Michael Johnson is doubtful with an abdominal injury. The England U21 midfielder recently unerwent surgery on the problem but it is still causing him some discomfort and he was advised to rest this week.
Stephen Ireland must serve the last match of his three-match ban so Sven will have to choose between Geovanni and Gelson Fernandes if Johnson is ruled out.
Geovanni would give City a more attacking edge and Fernandes more defensive, so the decision will come down to how Sven chooses to approach the game.
The Blues are looking for their first away win in the league since the opening day at West Ham and victory would put us into the top 3 with Chelsea not playing Blackbun until Sunday.