VANCOUVER, British Columbia—Nathan Chen rebounded from a surprising struggle last weekend at Skate America to top the short program Friday at Skate Canada. Third last week in Las Vegas after winning 14 straight events since March 2018, the 22-year-old American scored 106.72 points to open the competition at Doug Mitchell Thunderbird Sports Centre. “Any time, both in practice and competition, when you don’t do well, I want immediately to get another opportunity to try,” Chen said. “I don’t know if it’s going to be successful or but I want that next opportunity. I’m thrilled I have this opportunity to try this again rather than wait three or four weeks.” The three-time world champion who won the Grand Prix Final in Vancouver in 2019, Chen had a whooping technical element score of 60.29. Fellow American Jason Brown was second at 94.00, and Canada’s Keegan Messing was third at 93.28 in front …