South Africa have finished third in the past two Rugby Championships and have also suffered notable defeats to the likes of Ireland, England, Wales and Italy over the past two years, leaving them sixth in the world rankings - their joint-lowest ever position.
New Zealand also inflicted the Springboks' heaviest ever defeat during Allister Coetzee's ill-fated reign, which was brought to an end in February when the 45-year-old was sacked as head coach.
Rassie Erasmus has since taken the reins, and Pienaar - who led South Africa to arguably the most iconic World Cup triumph in the competition's history in 1995 - insists that there is still time to turn things around.
"It's a rebuilding phase. The last two years that we want to forget but it will stay with us. So there's hopefully a bit of a regime change. There's wonderful talent and hopefully putting it together, this year will be our year and leading up to the World Cup next year," he told Sports Mole.
"The World Cup is always a four-month project. Everybody always says it takes four years - it doesn't, it's four months because you don't know who's going to be fit. There are new stars coming through. You have to change your game, not to be predictable. So I've always said the World Cup is a four to five-month project."
PIenaar won 29 caps for South Africa between 1993 and 1996.