Sven expecting Isaksson exit as he goes with his Hart

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After switching the two men around over the past month, Eriksson vowed to make a final decision on his first-choice in the aftermath of Tuesday's Carling Cup defeat by Tottenham.

Although Hart was beaten twice by Spurs at Eastlands, Eriksson saw enough ability in the England Under-21 star both this week and in his eight previous first-team appearances for the Blues this term to place his trust in the former Shrewsbury man.

Ironically, the 20-year-old had already left City's Carrington training base when Eriksson reached his conclusion, leaving the former England boss to break the bad news to Isaksson, whose future surely now lies elsewhere.

"I have spoken to Andreas and obviously, he is not very happy," said Eriksson. "I have told him it is up to him whether he leaves or stays and fights for his place.

"It was important for everybody that I came up with this decision before the transfer window opens in January.

"I don't know what Andreas will do but if he comes back and tells me he wants to go, I will not be surprised and I will understand."

Eriksson's decision is a massive vote of confidence in Hart, who was signed by the Swede's predecessor Stuart Pearce in May 2006.

The transfer fee could reach £1.5million depending on how far Hart goes in the game. And, despite his tender years, Eriksson is convinced full England honours are not beyond the realms of possibility.

"Joe will be my number one for the foreseeable future, which just shows how much belief I have in him," said Eriksson. "I strongly believe he will be a great goalkeeper. He is only 20 and he will get better and better.

"He is the England Under-21 keeper and he has a great future."

With Isaksson ready to quit, Cardiff are bracing themselves for the recall of Kasper Schmeichel, who joined the Bluebirds on loan from City in October.

Eriksson is yet to decide whether to reinforce his goalkeeping options should Isaksson quit in an attempt to safeguard his future with Sweden's Euro 2008 squad.

However, more new faces are expected in addition to the loan deal which has seen Mexico international Nery Castillo end his unhappy spell at Shakhtar Donetsk.

Eriksson made his first approach for Castillo in August, only for that bid to fail as the 23-year-old completed a £13million switch to Shakhtar from Olympiakos.

But his interest remained and when he heard the first whispers of Castillo's unhappiness in the Ukraine, where he played only eight league games and failed to score, the City manager decided to make another move.

This one has been far more successful, even though Castillo had to pay a substantial portion of the loan fee himself to get the deal through.

"I have never seen that happen before, which just shows his commitment to the club," said Eriksson.

It was planned for Castillo to make his debut in the January 2 meeting with Newcastle at St James' Park.

Instead, red tape could delay his official signing by 24 hours, meaning he would not be able to play until the following weekend's FA Cup tie at West Ham.