Ana Ivanovic joins Twitter, is awkwardly engaged by Rafael Nadal

USA TODAYAna Ivanovic joins Twitter, is awkwardly engaged by Rafael NadalUSA TODAYFormer No. 1, Grand Slam champion, ex-Adam Scott squeeze and Sports Illustrated swimsuit model Ana Ivanovic made an inauspicious debut on Twitter this week, when her social media debut consisted of a single letter. Ana Ivanovic (AnaIvanovic) on Twitter.