However, the addict is thought to have broken the rules and he could now be in jail until early 2010.
"Blake did a runner. He turned up in hospital and hell broke loose - everyone was totally shocked," the Sun quoted a source, as saying.
"He was asking Amy to forgive him. As he was going back inside anyway he felt he didn't have much to lose," the source added.
Fielder-Civil was due to leave rehab at the end of the month but it is understood he will now go back to prison.
A source said: "If he had stayed in prison last month rather than taking the rehab option he was set to be released at the end of this month. He's blown it."