Andreescu wins Rogers Cup as Serena Williams retires due to injury

Canadian teenager Bianca Andreescu won the Rogers Cup after Serena Williams was forced to retire with a back injury while trailing 1-3 in the first set in the final on Sunday. "I’m sorry I couldn’t do it today. I tried but I just couldn’t do it," Serena said. "It’s been a tough year but we’ll keep going," she added.