MASON (AP) — Wimbledon champion Roger Federer is out of the Western & Southern Open because of a back injury.
The 19-time major champion says he “tweaked” his back last week at the Rogers Cup in Montreal.
His withdrawal comes on the first full day of matches.
This U.S. Open warmup has now lost five of the top six players in the men’s rankings. With Federer out, Rafael Nadal will return to Number 1 when new ATP rankings are released August 21st.