Stock futures fell in the after-hours session, with Dow futures down more than 200. The Dow closed down 181 Tuesday at 17,919, and the S&P 500 was off 9 at 2,119.
"How Apple handles this area tomorrow is key," said Redler. "You also have Microsoft down." Both Apple and Microsoft are in the Dow, and they are the most heavily weighted stocks in the Nasdaq 100. Redler said Apple, along with Google, Facebook and Netflix had been a key positive for the market.
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"We'll have to see what happens with Amazon.com (earnings Wednesday)," said Redler. "Apple could be taken out of the mix, and whereas there's not that many leaders in the mix, it could be a headwind."
Steve Massoca of Wedbush Securities said he also is watching the $119 areas on Apple. "This is an outsized portion of the Nasdaq, S&P and Dow. All of those indices will be down," Massoca said. But he said Apple's earnings performance was not really that disappointing.
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"The stock got run up 10 bucks on the basis of whispers and things," he said. "This is a company that has a history of sand bagging the numbers, and then it comes in and beats. ... It didn't beat enough, and you had $10 of air pumped into it in the last four days."
Apple forecast fiscal fourth-quarter revenue below estimates, and its earnings beat was relatively slim. The tech giant's earnings of $1.85 per share topped the estimate of $1.81 per share, the narrowest beat in two years.
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Apple's fourth quarter revenue projection of $49 billion to $51 billion was shy of the analysts' average estimate of $51.1 billion, according to Thomson Reuters. Still Apple did sell 47.5 million iPhones in its third quarter, up more than 30 percent but the Street had hoped for more.
Wednesday earnings include Boeing, Coca-Cola, Abbott Labs, AutoNation, St. Jude Medical and Six Flags before the opening bell. After the bell, American Express, Qualcomm, Texas Instruments, F5 Networks, Cheesecake Factory, Discover Financial, Newmont Mining and Sallie Mae report.
Also mortgage applications are reported at 7 a.m. ET and existing home sales are released at 10 a.m. FHFA home price data is reported at 9 a.m.
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