Swimmer Magnussen missed out on gold by a fingertip in the 100 metres freestyle on Wednesday, robbing Australia of their strongest title chance and leaving the team facing their worst performance in the Olympic pool for 20 years.
Like Magnussen, 100 metres hurdler Pearson is a world champion with by far the quickest time of the year in her event who has embraced the favourite's label and suggested she could also break the world record in London.
Pearson, though, flatly rejected the comparison with her 21-year-old compatriot.
"We're completely different athletes," Pearson told a news conference on Friday.
"I've done this before. I'm a very experienced athlete, I've been competing for Australia since I was 16 years old. I've been to an Olympics, I've been to four world championships now, and two Commonwealth Games.
"I know how to keep myself grounded, I know how to stay focused and I know how to stay hungry and they are probably the three key main areas that keep me so fast.
"I know these girl can beat me because they've done it before. I know it's going to be tough, it's the Olympic Games, it's never easy."
Australia's swimmers, who won six golds and 20 medals in total at the Beijing Olympics four years ago, usually provide the bulk of the country's medals at the Games.
After Wednesday night's disappointment they had just one gold in the women's 4x100 freestyle relay along with five silvers and two bronzes.
The manner in which some of the swimmers have accepted their silver medals has also caused discomfort back home, particularly the tears shed by 100 metres backstroke runner-up Emily Seebohm.
"An Olympic medal is fantastic no matter what colour it is, I'm going out to win gold but I'd much rather have a medal than fourth place," said Pearson.
The 410-strong Australia team had come to London hoping to spoil Britain's party, continuing the fierce sporting rivalry between the two countries that goes back over a century.
While Britain got a boost on the eve of the Games from a first Tour de France cycling title courtesy of Bradley Wiggins, Australia's 2011 winner Cadel Evans finished seventh.
As Wiggins was cycling down the Champs Elysee in triumph, Australian golfer Adam Scott was blowing a four-shot lead over the last four holes at the British Open to miss an excellent chance of claiming his first major.
After the surprise relay title on the first day of competition in the pool, there has been disappointment after disappointment.
Pearson races at the Olympic stadium next Tuesday and said she felt no extra pressure because of the swimmers' lack of gold medals.
"I don't see it as pressure, I see it as support," she said. "Everyone wants me to win and that's exactly what I want to do.
"I don't want to go out there and get second either but at the same time I can't guarantee winning but I'll be doing my very best to come away with the gold."
Australia's Chef de Mission Nick Green said Australia's showing in the pool reflected a greater distribution of gold medals among the competing nations than had existed in previous Games.
"We're at the Olympic Games, it's a very competitive environment," he said.
"If we don't win more than one gold medal, we'll all be disappointed but so will the swimming team because they have lofty expectations."