(CNBC) — U.S. stocks closed lower Monday, with materials lagging, extending Friday’s declines after the Brexit surprise.

The major indexes came off session lows as the close neared. Traders said there were more buy orders at the close when some had expected to see selling. They also said the market was lifted by investors buying stock to cover short positions.

The euro and pound traded lower, with the U.S. dollar index rising more than 1 percent in afternoon trade to pressure dollar-sensitive assets.

“I think you’ve got some technical damage here and it’s to be expected. The size of the moves in the currency markets are order-of-magnitude larger than the stock market’s,” said Art Hogan, chief market strategist at Wunderlich Securities. “That’s a hard thing to catch up with, and the knock-on effect that it has.”

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