The 27-year-old lock forward says that for years the Cheetahs have struggled to shed the tag as a "small-union" team, something they can put to rest with their third successive appearance in a Currie Cup Final on Saturday.
Pieterse, who joined the Cheetahs from the Lions in 2003, said a lot has changed in the past three years.
"When I first arrived here [in Bloemfontein] there was pretty much this small-union syndrome surrounding the Cheetahs," Pieterse told rugby365.com.
Even though the Cheetahs regularly reached the play-offs, they were not regarded as one of the big players on the domestic scene - simply because they had, at that stage, only won the Currie Cup competition once.
But that perception has slowly changed over the last few years and especially after Rassie Erasmus took over as coach last year - when the Bloemfontein-based outfit won the Currie Cup for the second time in their history.
"When we played in the Final in 2004 we were just so glad that we just reached the Final that we actually lost site of the Final itself," Pieterse said.
"The Cheetahs did very well under [previous coach] Peet Kleynhans [reaching several semi-finals and a Final], but it just showed that Rassie [Erasmus] brought a bit more professionalism and let the guys concentrate a bit more on their own job," he said about last year's Currie Cup triumph, in the first year of Erasmus' reign as coach.
"The biggest change (since my arrival in 2003) was Erasmus's professionalism. There may still be people who tag us as a small union, but the fact that we are playing in our third successive Final shows there is something big here," he added.
Pieterse says the fact that this is his third successive Final is what makes this year's showpiece so special.
"Also, the fact that the Boks are not present makes the games so much more competitive," he said.
"And it is always nice to face a team like the Bulls in the Final, especially at your home ground."
Pieterse said the Cheetahs will have plenty to prove after the Bulls beat the Cheetahs twice in the regulation season.
"They certainly overpowered us, and now we have a point to prove. But they are a good team and they will throw everything at us, it will be very tough."
Pieterse also felt that the Cheetahs fell somewhat short in the physical department in those two defeats, almost being hesitant to get involved.
"That [being hesitant] was certainly true in the first game in Bloemfontein. We really didn't stand up to them like we should have. We have worked very hard on that and spoke about it. In the second game it was better, but still not where we wanted it.
"We know the Bulls are a very physical team and they are just as determined to win. No doubt they want to come beat us here on our home ground. I think they will 80 percent more physical than they were in that first game in Bloemfontein."
But Pieterse is ready for whatever the Bulls will throw at them this time round.
"It is always nice and enjoyable when it is tough. It is nice when you sit after the game and say we stood our ground against them. You must be able to show a scar or two after the game."
Pieterse added that it is every young boy's dream to play for his province, but a Final a home is the first prize.
"You support your team as a youngster, you see the big stadiums with all the people and sometimes we [the players now playing at this level] lose site of the fact how people aspire to this. It is incredible to be able to run out in front of your home crowd.
"I've never had the privilege to play in a home Final and that is what makes this one so special. I can just imagine how it must have been for the Bulls to play in the Final at home for three, four years in a row. It is an incredible honour and privilege."
He says he is enjoying his rugby at the Cheetahs, especially now that he is one of the senior players, where in his days at the Lions he was merely a sometimes replacement.
"At the Lions I only got game time when there were injuries, playing behind players like Kleinjan Tromp, Willem Stoltz and Jannes Labuschagne. Now I fulfil a completely different role."
Like every rugby player in the country he does dream of one day getting that call from the national coach to say he has made it.
"Everybody would want to play for the Boks, even just one game. But it has never been a focal point for me. If it happens it will be great, but if it doesn't happen then it won't be the end of the world.
"I enjoy my rugby and it is a very nice set-up here at the Cheetahs. Rassie [Erasmus] knows how to keep your feet on the ground and keep you motivated."
By Jan de Koning