NEW YORK (TheStreet) --The Dow Jones Industrial Average, S&P 500, and the Nasdaq all closed in the red on Monday, the first negative day in five trading sessions. Additionally, the Russell 2000 closed lower 1.29%, ending its 15-day winning streak.

"Remember what led the charge; the Russell 2000, that's down the most. Transports, that's also down more today, and bank stocks are also down, that makes some sense," CNBC's Bob Pisani said on "Closing Bell" this afternoon.

Oil, however, rose 1.8% to close at $46.89 per barrel.

"The market seems to be anticipating that something is going to happen. Why? I don't understand," Pisani said about the OPEC meeting on Wednesday.

Putting the financials in focus, Pisani pointed to the decline in the SPDR KBW Bank ETF  (KBE) on Monday.

"Remember, banks had their big run up in the first two weeks [after the election], and now you see they are flattening out," he noted.

"Other groups have already declined; pharmaceuticals stocks, if you look at the PJP, had big runs up in the first few days after [the election], but you can see pharmaceutical stocks have [since] been declining," Pisani said.

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