* TSX down 9.75 points, or 0.07 percent, to 13,024.63
* Eight of the TSX's 10 main groups were lower
TORONTO, Dec 22 (Reuters) - Canada's main stock index dipped on Tuesday, including losses for financial sector shares, while energy stocks seesawed despite a rally in crude oil prices and mining stocks rose.
The most influential movers on the index were Royal Bank of Canada, which fell 0.8 percent to C$73.94, and Bank of Montreal which was 1.1 percent lower at C$77.82.
Brookfield Asset Management Inc rose 0.2 percent to C$43.73. Australia's antitrust regulator said it will consider a watered down version of the infrastructure giant's $6.5 billion bid for freight firm Asciano Ltd, reviving the prospect of a deal.
The overall financial services sector fell 0.6 percent.
At 10:58 a.m. EST (1558 GMT), the Toronto Stock Exchange's S&P/TSX composite index fell 9.75 points, or 0.07 percent, to 13,024.63, with eight of the index's 10 main groups in negative territory.
Dominion Diamond Corp surged 22.5 percent to C$14.06. It said it looked forward to having an open dialogue with a group of investors led by Canadian hedge fund K2, who believe that the diamond miner's policies have unduly hurt its share price.
Centerra Gold fell 2.6 percent to C$7.00 after Kyrgyzstan's government said it had stopped talks with the company on restructuring their joint Kumtor project because the current agreement "ran counter to the country's national interests."
The overall materials group rose 0.7 percent.
Energy stocks rose 0.2 percent, led by pipeline companies.
TransCanada Corp rose 1.8 percent to C$45.46, while Enbridge Inc was up 1.2 percent at C$44.10.
In contrast, Suncor Energy Inc fell 0.6 percent to C$35.49.
U.S. crude prices were up 1.2 percent to $36.23 a barrel, while Brent crude added 0.3 percent to $36.45.
Valeant Pharmaceuticals International Inc rose 2.2 percent to C$155.35. (Reporting by Fergal Smith; Editing by Meredith Mazzilli)