Dethroning king of clay is world No. 1's toughest test.
Houston champion is king of the hill.
Former No. 1 traveled to Miami to talk hip health with Bob Bryan.
Three-time Grand Slam champion talks rivalries and tennis heroes.
World No. 42 adds former major finalist to coaching team.
Clay season just got brighter.
The American has been through multiple surgeries to her right arm and recently had a plate removed.