Investor concerns in the U.S. stock market of a "crash-landing scenario" for the Chinese economy are misplaced, former Morgan Stanley Asia Chairman Stephen Roach said Thursday. "I think those fears are vastly overblown," he said.

Growth in China has slowed, Roach acknowledged in a CNBC "Squawk Box" interview, "but it's not going in for a crash … and that will present, I think, an opportunity for shares to re-evaluate the China threat, big time."