Strong earnings from Nike helped lift the Dow in opening trade Friday as markets eyed ongoing talks to avert a Greek debt default.

Five minutes into trade, the Dow Jones Industrial Average was at 17,948.22, up 57.86 points (0.32 percent).

The broad-based S&P 500 rose 1.36 (0.06 percent) to 2,103.67, while the tech-rich Nasdaq Composite Index dropped 6.76 (0.13 percent) to 5,105.43.

Athletics footwear and apparel maker Nike jumped 4.3 percent to lead the Dow as earnings for the quarter ending May 31 rose 21.6 percent to $865 million.

Greece's international creditors offered Athens a five-month, 12-billion-euro ($13.4-billion) extension of its bailout program but said it must seal a deal this weekend to avoid an IMF default next week.

The Shanghai Composite Index fell 7.4 percent, part of a big pullback in the past two weeks in part due to concerns about market overvaluation.

But the turbulence in China has not spread, suggesting global investors "recognize the Shanghai Composite is operating in a crazy world of its own," said Briefing.com analyst Patrick O'Hare.