What stocks does a five-star fund manager think about on a less-than-stellar day?
It's a good question for Tom Ognar, manager of Wells Fargo's Advantage Growth Fund. The fund is up an average of 15.26 percent per year over the last five years.
"These are troubling times, and so, let's take that into account and have a game plan," he told CNBC.
He urges investors to "stress-test" their portfolios, watching out for those companies that are lowering their guidance, and those companies that are able to offset challenges with unique initiatives.
One company that survives his stress test is medical device firm St. Jude Medical.
"That really fits into our game plan, which is, find areas where you're not really dependent on the consumer, find areas where the U.S. economy's not going to drive the opportunity set for the company's fortunes, and St. Jude is a good example of that," he said.