For the S&P 500 (^GSPC), "1,910 is going to be the 100-day moving average. That's going to be where at least it'll stop and look and feel if it has anything there," he said on CNBC's " Halftime Report ."
The next level of support is 1,857, its 200-day moving average, Polcari added.
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"I don't think it's going to, but clearly until it starts to build a base somewhere in here, until the market gets over the erratic behavior that it had yesterday, it's going to continue to flounder," he said.
Ritholtz Wealth Management's Josh Brown noted that $4.8 billion have exited junk bonds .
"I think junk was one of those areas that was priced to perfection," he said. "Everybody was hiding out in there and trying to beef up the yield in their portfolios."
But the selloff was a sign of something looming on the horizon, Brown added.
"The big money is preparing for higher rates. It's not a prediction. It's not a call. It's not something that's imminent, but they are shifting their portfolios," he said. "People are starting to consider the possibility of not having quite as much junk, quite as much of these high-dividend stocks in their portfolio. They're looking for something else to do."
Citigroup Head of Markets for North America Suni Hartford also said that she saw a shift occurring.
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"I tend to say it's not a correction; it's a direction, if you will," she said. "The market has known this was coming. This is the reaction to higher rates. It is finally that moment when we expect things to move forward with that direction in mind. We are seeing it across the board, asset sales. It's kind of a risk-off trade right now, but it's not panic.
"We don't see panic in any asset class, even high-yield. Certainly not equities. It feels more like a repositioning to us."
-By CNBC's Bruno J. Navarro