It was only five sentences, but it was enough to startle the market.

On Thursday, two Goldman Sachs analysts essentially advised clients to bet that the stock market will keep going down.

In a research note, Noah Weisberger and Aleksandar Timcenko recommended shorting the Standard & Poor's 500 index, a key measure of the overall stock market. When investors short a stock, they are betting that its price will fall.

The note was released at 10:46 a.m., when the S&P 500 was trading around 1,350, down six points for the day. By late afternoon, as the Goldman note made its rounds, the S&P fell to 1,330, down 26 points, or 2 percent. The Dow Jones industrial average fell more than 200 points.

The Goldman analysts cited a 10 a.m. report from the Philadelphia branch of the Federal Reserve, which showed a sharp contraction in manufacturing in the Northeast, and said it "provides further evidence that weakness has extended into June."

The analysts also noted the continued signs of sluggishness in the U.S. economy, a cooling off of China's previously red-hot growth, and infighting over Europe's heavy debt burden. They predicted that the S&P could fall to 1,285, which would be about 5 percent below Wednesday's closing price.

"The market," they wrote, "will need to confront a deteriorating growth picture near term."