TORONTO (Reuters) - Toronto's main stock index fell for a second straight day yesterday as worries over Europe's fiscal troubles outweighed a brief shot in the arm provided by a more upbeat US Federal Reserve outlook.

Financial and energy shares were among the heavyweight sectors leading the way lower, down 1.38 percent and 0.55 percent, respectively.

Royal Bank of Canada, the country's biggest lender, dropped 1.34 percent to C$60.58, while Canadian Imperial Bank of Commerce lost 1.25 percent to C$74.49. Suncor Energy, Canada's biggest oil producer, dropped one percent to C$33.57.

Nervousness over the fragility of sovereign debt in the euro zone spurred a flight to safe-haven assets after Spain was hit by a credit rating downgrade yesterday, following downgrades to Greece and Portugal on Tuesday.

"The main thing that's driving the markets in the last few days is the fear of what's happening in Europe and how far is that contagion likely to spread," said Michael Sprung, president at Sprung & Co Investment Counsel.

The Toronto Stock Exchange's S&P/TSX composite index finished 69.85 points, or 0.58 percent, lower at 12,076.89. Nine of the index's 10 main groups were down.

The index briefly popped into positive territory after the US Federal Reserve left interest rates unchanged near zero and offered a brighter economic view.

The heavyweight materials group gained 1.35 percent, well-supported by broad gains from gold producers, with bullion prices rallying to their best level in almost five months.

Goldcorp was ahead 3.17 percent at C$42.99, while Agnico Eagle jumped 3.36 percent to C$64.24.

Barrick Gold added 2.6 percent to C$42.51, rising with the broad gold rally and on the back of a first-quarter profit that more than doubled to a record high.