But with Swedish number one Andreas Isaksson now fully fit and kicking his heels on the sidelines, Sven must decide who his first-choice goalkeeper is.
After Hart let in 6 at Chelsea, Sven gave Isaksson his 1st game of the season in the Carling Cup clash at Bolton and although none of the Chelsea goals were Hart's fault, Isakkson was expected to remain between the sticks.
But Hart was back in when City resumed league action with a 1-0 win over Sunderland and kept another clean sheet in the goalless draw at Portsmouth.
The England U21 keeper was also named Man-of-the-Match at Pompey, giving Sven a keeper dilemma as Isaksson, an experienced international, is said to be none too happy about being kept out by a rookie.
"Joe is doing extremely well," said Sven. "It's good for him to have another chance in the league after that last away game and he made some great saves."
Hart, who remains in the latest England U21 squad, insists the Chelsea defeat was a one-off and has shown his gratitude to Sven for keeping faith in him.
"We showed as a team at Pompey that what happened at Chelsea was a one-off and a fluke. That is three clean sheets in succession now and we have shown we have the spirit to bounce back, " he told the City website.
"The last three performances have been huge for us. Not maybe in terms of flare and excitement but in showing that we can dig and graft and that the Chelsea game really hurt us.
"I don't think that I could be blamed for what happened at Chelsea but I suppose it would have been easy for the boss to drop me. That he didn't just added to my confidence.
"I just get on with what I have to do and try to do it the best that I can," he added. "I have possession of the shirt and it is up to me to keep it for as long as I can."
As Hart said, Sven's policy has given him a huge confidence boost, but I worry how long he will continue to leave him in there for. Eventually, I think he will be caught out of his depth and that is bound to set his confidence back.
Although Hart has done well and deserves to have kept his place so far, I think Isaksson is still a better keeper. He is the better option in the long run and the sooner he becomes first-choice again, the better.