Tesla's earnings beat—when Wall Street analysts expected a loss—didn't make a buyer out of RiskReversal's Dan Nathan.
"Elon Musk says what he wants to say," Nathan said. "Don't forget, people. This is the guy who said in the last couple of months that this stock's expensive here."
After Wednesday's market close, the electric-car company posted earnings of 2 cents a share vs. an estimated 1-cent loss, sending shares 7 percent higher in after-hours trading.
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On CNBC's "Fast Money," Nathan said that he held "a small defined-risk trade in options" and expected the stock to decline.
"I think you're going to see $200 over the next couple of weeks," he said. "I think the chart has been waning since the highs earlier in the year, so I just wouldn't chase it right here."
Stuart Frankel's Steve Grasso said Tesla stock was still a "buy."
"You can chase the stock here," he said. "It went from—gross margins—17 percent, 25 percent, now above 28 percent. GM, Ford? They're at 18 percent."
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Grasso said the earnings beat was especially notable in light of weakening China growth and oil prices getting slammed.
"It's very volatile, but the way it's been holding this $226 level on the 200-day, I think you use that as your stop-loss," he said.