Let's consider the current state of the U.S. Open men's draw.
The top half of the draw is relatively intact. Both No. 1 seed Rafael Nadal and in particular No. 3 Roger Federer have looked vulnerable, but everyone's preferred semifinal is still happening as of now. In their way are the likes of No. 6 Dominic Thiem, No. 9 David Goffin, No. 18 Gael Monfils and No. 24 Juan Martin del Potro—a fairly robust, if slightly thin, list of challengers. A couple big names are out earlier than expected, like Nick Kyrgios and Grigor Dimitrov, but everything on this side is still pretty normal.