Del Potro - 12 months on from US Open crown

Question

In September last year, Juan Martin del Potro became a Grand Slam champion, but the year since has been dominated by ongoing wrist problems that will force the 21-year-old to miss his title defence. More at http://blogs.bettor.com/Juan-Martin-del-Potro-a-year-on-from-the-US-Open-title-a22979.