Long-term growth would come from such initiatives as getting Pandora's streaming music service into one-third of all new cars, something that Spotify and Apple don't offer, Mahaney said.
"If Apple comes out with a better mousetrap, it's an issue—a real issue for Pandora. We think that that's likely not going to happen, that Pandora's got enough loyalty amongst its users. By the way, they do have a growth driver that Apple doesn't have, which is automotive integration," he said.
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"And they've got a service that's free, and we think has got very compelling features to it. So, it could be undermined. We're going to take the other side of that bet. We're going to stick with Pandora."
Mahaney said that Pandora would likely stave off challenges from Apple's iTunes and Google's Play.
"The irony of all this is Apple is launching an ad-supported model, and Google launched a subscription-supported model. But nonetheless, Google's out in the market, and we haven't seen it impact Pandora to date," he said.
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"We think Pandora's fundamentals will work through this, and the stock will rise. But that's going to be the controversy, probably weigh on the stock for the next three or four weeks."
—By CNBC's Bruno J. Navarro. Follow him on Twitter
—CNBC's Katie Young contributed research to this report. Follow her on Twitter:
Trader disclosure: On Aug. 26, 2013, the following stocks and commodities mentioned or intended to be mentioned on CNBC's "Fast Money" were owned by the "Fast Money" traders: Stephen Weiss is long AAMRQ; Stephen Weiss is short FB; Stephanie Link is long AAPL; Stephanie Link is long GS; Stephanie Link is long JPM; Stephanie Link is long WFC; Stephanie Link is long CSCO; Stephanie Link is long EBAY; Stephanie Link is long FB; Michael Murphy is long BAC; Michael Murphy is long C; Michael Murphy is long FB; As of 8/21 Jon Najarian is long AAPL; Jon Najarian is long EBAY; Jon Najarian is long GRPN; Jon Najarian is long MSFT; Jon Najarian is long QCOM; Jon Najarian is long MSG; Jon Najarian is long TOL; Jon Najarian is long JCP; Jon Najarian is long HLF; Jon Najarian is long CREE.