England stumbled to defeat in the recent Test series against the Springboks but Flintoff, 30, is confident the chance to gain quick revenge can inspire England to new heights.
Kevin Pietersen has already made a positive impression on the Test squad and Flintoff expects the new captain to have a similar effect on the one-day players.
"It's a pretty different team to the Test side and a lot of lads have come in wanting to impress and cement spots within the side so there's a freshness about the squad," he said.
"Kevin has obviously taken over as captain and everyone is eager to impress. England for a long time now have under-performed in one-day cricket and we've got a chance to address that now and hopefully put some performances in."
During Flintoff's 125-match career with England's one-day side they have continually under-performed and have not reached the deciding stages of a World Cup since reaching the final at Melbourne in 1992.
Their record in Champion Trophy tournaments is little better, although they did lose in the 2004 final on home soil, but with a new captain and rapidly-evolving side Flintoff hopes this current group can end the years of failure and finally perform on the world stage.
"It probably goes back further than just us," he stressed. "We got to the World Cup final in 1992 and since then we've never been consistent.
"We're definitely aware of that but we can't let it lie too heavily on us. We've got to go out there and perform and we're well aware of that, but we've got to do it consistently."
Victory in the series against South Africa would suggest a major turnaround in fortunes after winning just six out of the last 19 matches while the tourists have won 16 of their last 19, including winning their last nine in a row.
"They're the form side, they've beaten everyone they've come up against," conceded Flintoff.
"They are a formidable team in one-day internationals and it's going to be tough for us but we've got to test ourselves against these sides.
"We've beaten the best sides in the world before, but we've got to beat them over a period of time and not just in one-off games."
Having Flintoff back in their line-up will be a considerable bonus for an England team without Collingwood while left-arm seamer Ryan Sidebottom is yet to recover from the hip problem which has troubled him recently.