Coco Gaff Wobbles, then stole the show at the US Open
In the opening set of her third-round match against Elise Mertens on Friday, Coco Goff was erratic, frustrated and ending early, nothing like it was at the US Open earlier this week. Mertens, a 27-year-old from Belgium, was playing loose and aggressive, while 19-year-old American superstar Goff made error after error with every stroke. Goff,…