Puig upsets No. 7 seed Suarez Navarro, 6-3, 7-5; Muguruza tops Cibulkova, 6-2, 4-6, 6-2.
Mladenovic rallies for a 2-6, 6-3, 6-3 victory over top seed; Sock, Querrey, Johnson score straight-sets wins on men's side.
"I wouldn’t say it’s really open there... I think it’s back to the old lines like it was before," says world No. 5.
"It’s been a lot of frustration, anger and disappointment," said world No. 7.
The 21-year-old former NCAA champion earns U.S. Open wild card for third straight year.
Reviewing the big breakthroughs, altered allegiances and tool-time label on the tours.
Sela, Ferrer, and Rochus have proven that small ball remains viable in a sport trending taller.
As the players start to cross the pond, a look ahead at the last four tournaments of July.
The pros and cons of Big John. Plus: Saturday previews and Delpo hits backhands.