"Disastrous," reflected Walker with the kind of downbeat assessment usually reserved for Private Frazer in an episode of Dad's Army.
"It was my first taste of links golf in a schools match between Scotland and England when I was 15. I'd grown up playing parkland courses, and had just really started playing golf; it was just a totally different experience to what I was used to."
Walker has come a long way since those formative years, of course. This week, she will be back at Royal Birkdale for the Ricoh Women's British Open. And she will return as a tour champion.
Now in her fifth season on the Ladies' European circuit, the 27-year-old from Glasgow finally took a significant stride forward when she captured her maiden title, the Deloitte Ladies Open, in a play-off at the end of May. The spin-offs from that triumph are bountiful. Instead of joining the final qualify-ing scramble tomorrow, Walker's success fast-tracked her straight into a field of global stars which is headlined by newly-crowned US Women's Open champion Michelle Wie, who finished third as an amateur in the British event at Birkdale in 2005.
Walker has had a taste of the big time before, when she qualified for the 2011 championship at Carnoustie, and the former Scottish amateur stand-out is relishing the prospect of going head-to-head with the main movers and shakers of the women's scene.
"I made the cut on my debut and it was such an exciting week which whetted my appetite for more," she said. "These are the events you want to be playing in all the time. Of course, the goals have changed a wee bit now and I've set the bar higher. Winning on the tour gives you that belief that you can do better things; it's been a real spur."
Walker has been galvanised by that victory in the Netherlands. After an impressive start to life on tour, which was illuminated by five top-10 finishes over the course of the 2010 and 2011 seasons, the former St Rule Trophy winner had felt she was treading water over the last couple of campaigns.
"The last two years were a bit stagnant to be honest," she said. "I was always coming off the course feeling like I'd played better than I had scored. I was underachieving and that caused a lot of frustration. During that time though, I didn't change a thing. I kept with the same team that has always been around me [her coach, Kevin Craggs, remains a major influence]. As long as you have something that works, and you stick with it through thick and thin, then you become a stronger player."
That resolve and belief finally reaped the ultimate reward with a first tour triumph. "I'd led for the first two days and being in that position going into the closing round was something new to me," she said. "I enjoyed the whole experience though. I thrived on being at the sharp end. I didn't feel uncomfortable at all and it was important to feel like that. It was the realisation that you could do it."
Walker, whose long-term boyfriend Scott Henry was pipped in a play-off to the Madiera Islands Open just a fortnight before her own sudden-death win, will now take her newfound confidence on to the Major stage.
"I always enter each event trying to win," she said. "I don't want to be around just making up numbers. I definitely want to be a winner."