TORONTO - Premier Dalton McGuinty merged two massive ministries in a small cabinet shuffle Friday that put George Smitherman atop a new energy and infrastructure "super ministry" and in charge of several key Ontario mega-projects.

Former infrastructure minister David Caplan took over the Health and Long-Term Care files, while ex-energy minister Gerry Phillips remains in cabinet as a minister without portfolio.

McGuinty dismissed suggestions that he combined the two portfolios to satisfy Smitherman, who served not only as health minister and custodian of one of Canada's largest budgets, but also as his right-hand man and deputy premier.

"I think it's a great fit, it's a natural fit," McGuinty said. "And it's an essential part of our plan to grow this economy."

Smitherman's principal challenge will be overseeing the province's $26-billion plan to refurbish and replace its aging nuclear fleet, which includes building two new reactors.

Energy isn't entirely connected to infrastructure, but combining the two files seemed a good idea given the province's ambitious nuclear strategy, McGuinty said.

"It's a big job, but this guy is more than capable of taking on that responsibility."

Smitherman -- dubbed "Furious George" for his aggressive and often abrasive manner in the legislature -- is also in charge of billions of dollars in infrastructure programs across the province, including upgrades to roads and transit systems and building new schools and hospitals.

Caplan's promotion was also panned by critics, who say the heavy-set former smoker is ill-equipped to handle the health file.

But Caplan, 43, said he's focused on his new job, rather than what people are saying about his weight.

"My own conversations between me and my doctor are private matters, (as) they are for all of us, and they'll remain private," he said.

"I think as the premier's outlined today, he has the confidence in me based upon the track record that I showed over the course of the last 4 1/2 years and I'm going to fulfill the mandate that Premier McGuinty has set out for me."

Caplan will oversee one of the largest budgets in the country -- $40 billion this year -- accounting for nearly half of every dollar the province spends on programs.