The Proteas have arrived in India for the forthcoming World Cup, where they are rated only fourth favourites behind India, Sri Lanka and Australia.
Graeme Smith's side has just four players with World Cup experience - the captain himself, Jacques Kallis, AB de Villiers and Robin Peterson - and will be looking to reach the final for the first time.
Their five trips to the tournament have yielded three semi-finals, one quarter-final and a first-round exit on home soil in 2003.
Writing in the Cape Times newspaper, Tsotsobe said: "Let's address an issue that keeps rearing its head whenever a major tournament comes around, this issue of the Proteas being so-called 'chokers'.
"I feel, if you really support your team, you don't go around calling them names.
"In saying that, I understand that people have feelings, that it's their country and they love it and they want success, but one thing is clear, we're always giving our best.
"The feeling is that by concentrating intensely on the World Cup, pressure is created and that's where this issue of 'choking' comes up.
"That's why we're trying to change the mindset and people's perceptions. We want to show that our team culture is all about looking after each other and the emphasis is on building a team first and then focusing on the World Cup."
Left-arm paceman Tsotsobe is one of the rising stars of the team, taking 36 wickets in 19 matches at an average of 19.91 so far and featuring impressively in all three Tests against India over the summer.
During the one-day leg of the tour, he ended as the leading wicket taker with 13 in five games and is now aiming to take that form to the highest stage.
He added: "I have a couple of clear goals for the World Cup. I want to be the best bowler at the tournament and I want to improve my game as a bowler in those conditions.
"That's what I want to achieve, along with getting fitter and making sure that I'm in peak condition at just about the right time."
South Africa are in Group B alongside India, England, Bangladesh, Ireland, Holland and West Indies, who they begin their campaign against on February 24.