SOELDEN, Austria -- Nina O'Brien's rollercoaster ski career over the last three seasons includes a gold medal at the 2023 world championships and breaking her left lower leg twice.This weekend, the American starts yet another comeback season."In so many ways it's uncomfortable and nerve-racking, but on another hand it's familiar and it feels like my world and my family. Physically I feel ready, mentally I'm ready, and I'm excited to be here," O'Brien said on the eve of Saturday's World Cup opener in Austria, her first top-level race in more than 19 months.Born in San Francisco and grown up skiing in Palisades Tahoe and Burke Mountain, O'Brien has been racing on the World Cup circuit since 2016.Mishap struck for the first time in February 2022, when she badly crashed near the finish of her first Olympic race, the giant slalom at the Beijing Games. A gruesome compound fracture left her bone protruding from her leg and O'Brien needed four surgeries."When I came back from my injury in Beijing, I remember like having initially some good results and then struggling and feeling like that struggle was actually more painful," O'Brien said."When I went through this dip, it really hurt my heart. And so, just knowing that kind of return to racing and to peak performance isn't always linear is something that I'm aware of now."O'Brien found her way back again and teamed with Paula Moltzan, Tommy Ford and River Radamus to win win the team event at the 2023 worlds in France."That middle period of the season where I was struggling, I really did come out of it. And towards the end of the season, I was skiing some of the best GS that I ever have," she said.O'Brien had not mu ...