(Updates to close) July 28 (Reuters) - Australian shares...

(Updates to close)

July 28 (Reuters) - Australian shares snapped a three-day winning streak and ended lower on Friday, as investors grew cautious ahead of upcoming earnings as well as second quarter U.S. economic growth data.

The S&P/ASX 200 index (xjo) fell 1.4 percent, or 82.21 points to 5,702.8 at the close of trade, posting its biggest intraday percentage loss in four weeks. The benchmark closed down 0.4 percent for the week.

Markets were focused on second quarter U.S. gross domestic product data due later in the day for clues on the strength of the U.S. economy. Economists expect the data to show U.S. growth picking up to 2.6 percent from 1.4 percent in the January-March quarter. [MKTS/GLOB] [FRX/]

Financials and materials led the losses on the Australian benchmark index.

The "Big Four" banks each lost over 1 percent each, with the financial index .AXFJ dropping 1.7 percent.

The metals and mining index .AXMM fell 1.3 percent, with heavyweights BHP Billiton (BHP) and Rio Tinto (RIO) both posting their biggest intraday percentage losses in a week.

New Zealand's benchmark S&P/NZX 50 index (nz50) suffered broad-based losses, shedding 0.9 percent, or 72.21 points to finish the session at 7,639.51, its lowest close in two weeks. It lost 0.4 percent for the week.