Exhaustion

Friday's close outcome an exhaustion pattern. The pattern occurs when the open of the current day is above the high of yesterday. Means small trades/investors who are trading at the open , are anxious to place new longs or cover shorts. They are in panic.
The big guys identifying these behaviour and taking advantage of it by selling.
In the below SP500 Cash chart, you can see what happened few days after the pattern occurred. (The red dot above the price).