MANCHESTER, England (Reuters) -- Manchester United manager Alex Ferguson said he felt "fine" on Friday after undergoing hospital treatment for an irregular heartbeat.

The 61-year-old underwent a D-C cardio version, a controlled electronic shock, on Thursday and on his return to take United training on Friday dismissed media reports that his future as United boss was in doubt.

"I'm fine. It's just the sensationalism of newspapers. There's nothing you can do about that," Ferguson said.

"When any celebrity goes into hospital nowadays, someone is going to phone the newspapers and that's what's happened. "But I'm fine. There's no problem. I enjoy the work I do and that will continue. I've seen the doctor and he is fine about it." A statement from the English champions issued earlier on Friday said: "This (the treatment) was performed successfully on an elective basis yesterday. Everything is normal and Sir Alex feels fine."

British media reported that Prime Minister Tony Blair recently underwent similar treatment for the same ailment.

Ferguson is one of the most successful managers in British soccer history having guided United to eight premier league titles in the last 11 seasons and the 1999 Champions League.