Apple Inc shares were down about 5 percent in premarket trading on Wednesday, the first day after a rare quarterly earnings miss, but analysts called the results a blip and said it presented a buying opportunity.

On Tuesday, Apple stunned Wall Street with quarterly results that missed expectations for the first time in years as customers held off buying iPhones until the latest version came out in October.

One analyst called the results a black swan and said now was the time to buy shares, with Apple providing a stronger-than-expected first-quarter outlook.

We would be aggressive buyers of Apple this morning as we anticipate a big holiday season for the company, said Ticonderoga Securities analyst Brian White, who reiterated a buy rating on the stock.

White said he expected Apple's iPhone 4S to be another blockbuster iPhone product.

JP Morgan said in a note to clients the rare miss is explainable and could be an entry point for opportunistic investors. It added that shares of Apple are likely to come under pressure in the near term but that the company's sales overseas will ultimately boost its growth.

Apple's ongoing penetration of China and other emerging markets likely can be measured in years and stands to have a significant, positive impact on the growth profile, JP Morgan said in a research note.

Apple shares fell after its first quarterly earnings report under Chief Executive Tim Cook, who took over from Steve Jobs in August at a critical juncture for the company. Apple is battling Google Inc in the mobile arena, as well as other challengers such as Samsung <005930.KS> and Amazon.com .

Apple said it sold 17.07 million iPhones in its fiscal fourth quarter ended September 24 -- well short of the roughly 20 million forecast by analysts. The iPhone is Apple's flagship product, yielding some 40 percent of annual sales.

Apple shares fell $20.91 to $401.56 before the market opened.

(Reporting by Fareha Khan and Liana B. Baker, editing by Dave Zimmerman)