Former No. 1 rooting for second-ranked Swiss to regain top spot.
The two WTA stars light up the pages.
The 20-time major champion is angling for another massive milestone.
Coaching can be a game-changer said 2016 WTA Finals champion.
The Czech says he can no longer risk his health by playing Davis Cup.
Simona Halep will reportedly earn $2 million annually from Nike.
The Swiss could face Stan Wawrinka in the quarterfinals at the ABN Amro WTT.