Williams endured a difficult national team debut back in 2014 when South Africa suffered a 5-0 defeat to Brazil at FNB Stadium – a performance many critics used to question his ability at the highest level.
More than a decade later, the Mamelodi Sundowns shotstopper is now widely regarded as Africa’s best goalkeeper and Walters has backed him to once again prove his quality on football’s biggest stage.
"For me, we've always said it, goalkeepers mature with games, with experiences, with situations, and that has always been the thing," said Walters.
"And that's why I say, I think he's still got a good three, four years where he's actually still going to compete – I mean, look at Denis Onyango at 41, still playing good football.
"So it's always, for goalkeeping, it's about how did he recover from that and what did he learn from that? Did he take it as a knock or did he say, look, this is something that's actually going to help me grow as a player, as a footballer, as a goalkeeper."
Walters added that Williams’ transfer from SuperSport United to Sundowns four years ago was simply the cherry on top.
"Obviously his mindset and then the move to Sundowns also helped a lot for his career as well because then he took on a lot more responsibility, whether it was the Champions League, continental or the club, and then the armband as well," he added.
"So I think all of those things has really helped him and groomed him to become a very good goalkeeper, and I think he could still be in the top 20 goalkeepers in the world, definitely."