Nike Inc., the world's largest sporting-goods company, surged the most in more than 20 months after easing investors' concerns that its profitability and business in China were weakening.

The shares rose 9.5 percent to $58.69 at 9:40 a.m. in New York for the largest intraday gain since June 28, 2011. Nike had advanced 3.9 percent this year through yesterday, compared with an 8.4 percent gain in the Standard & Poor's 500 Index.

Price increases enacted last year finally paid off for the Beaverton, Oregon-based company as its gross margin widened for the first time in nine quarters. Meanwhile, the company reported that orders for the Nike brand in China, excluding changes in currency exchange rates, gained after sales there sank 10 percent last quarter for a second straight decline.

“Nike is firing on all cylinders right now,” said Brian Yarbrough, an analyst for Edward Jones & Co. in St. Louis, who has a hold rating on the shares. “They've been talking about, for several years now, expecting gross margins to eventually turn. And now it looks like that has played out.”

Eoin Treacy's view A disappointing earnings report checked Nike's advance almost a year ago and the share spent much of the intervening time ranging. The fact that the company was able to come through today with both stronger growth and earnings is a testament to the company's management.

The share rebounded to post new all-time highs today and a sustained move below the 200-day MA would be required to question the consistency of the medium-term uptrend. (Also see Comment of the Day on March 12th).