Eighteen-year-old Meghan Rutledge was enjoying the race of her life as she charged towards victory in the WMX women's motocross race at the X-Games.
And with the win in the bag, Meghan decided to celebrate by fist pumping as she went over the final jump of the race in Los Angeles.
It seemed like a good idea at the time. But it wasn't.
Taking her hands off the bars also took Meghan's eye off the ball momentarily, causing her to be just slightly unbalanced as she landed. She might have got away with it had there been a long straight ahead, but instead she faced a tight hairpin bend before the finish line - and she went down.
Fellow rider Vicki Golden couldn't believe her luck as she stormed past to win, with Meghan even missing out on a podium place despite scrambling to get back upright.
"I was out there leading. I'm really young. I've never led an X-Games before. I celebrated a bit too early and made a mistake, unfortunately, which gave Vicki Golden an opening to take first again," Rutledge told ESPN after the race. "If I had stayed on the bike, there was no way I could have lost. I had one straight to go. But, you know, mistakes happen."
Indeed they do, and race winner Golden - who had been hot favourite to win - was sympathetic.
"I came around the corner before the ramp in the final lap and heard the crowd scream, then went over the ramp and saw she was on the ground and that was all I knew," she said. "It was a last-minute, stressful race and I'm just happy and blessed to be out on top… She's young and she's still learning; we're all still learning. It all comes in time."