"I know now that I can perform under pressure and that's really good for me for London," Walker said. "The pressure was on in the quarter because if I didn't make it out of the quarter then that was my spot gone. And there was pressure not to crash out in the semifinal so I had to stay on my bike and ride smart.
"Performance-wise I an ecstatic considering I've been a week back on the bike and managed to get the hole-shot [first to the first corner] against the best riders in the world. Once my fitness is back up to where it was before the accident and a lot more hard work, then I will be confident of my chances."
Meanwhile fellow Kiwi Marc Willers, after dominating his semifinal, crashed in the final while attempting a brave passing move on defending champion Joris Daudet.
Willers, third at the world championships in Copenhagen last year, impressed with three wins in his qualifying moto and recorded the day's fastest time. He had a poor quarterfinal but made it through in third place before nailing his gate on the way to win his semifinal.
Willers was a fraction off out of the gate in the final but cut back under Maris Strombergs on the first corner to push up to third. He tried a similar manoeuvre on the next corner on Daudet but clipped his back wheel and crashed, bringing down two others.
"Out of the start I felt someone blow straight into me and I didn't get down the hill as fast as I wanted," Willers said. "I thought I could push into that last turn but Joris saw me coming at the last minute and cut over and I went down instead of him.
"I just didn't want to settle for another third place. I figured I had a chance of second and had a go. Second's as good as last so I thought it was worth going for. I've got to nail my consistency more. I started the day off great, then had a bad one in the quarter, a great one in the semi and a not so great one in the final."
Australian Sam Willoughby took out the world title, with several top hopes missing out on the final and time trial winner Connor Fields (US) crashing.
Promising Kaiapoi rider Trent Jones had to settle for fifth in the junior elite men's final after winning his semifinal.
The sole medal for the New Zealand team on Saturday went to Rangiora's Tahlia Hansen in the 15 years challenge class, with some age group racing staged alongside the elite finals day. Hannah Sarten (New Plymouth) was sixth in the 16 years girls and Cody Merito (Te Awamutu) eighth in the 15 years finals.
The championships will be completed with Challenge (age group) racing overnight in the Cruiser class, for the larger 61cm wheel base bikes.