Paralympic swimmer Lauren Steadman has fellow Briton Faye McClelland in her sights at this weekend's ITU World Triathlon Series event in Hyde Park.
The pair battled it out at the recent World Series event in Yokohama, with McClelland triumphing by 11 seconds.
And they face each other again on Saturday with Steadman aiming for the scalp of the four-time world champion.
"It will take courage and hard work to beat her," Steadman, 21, told BBC Sport.
"Faye is a tough racer and has a lot of experience but she knows I am hunting her down.
"She has always beaten me by quite a distance but Yokohama was the closest I had come, which was a surprise given my lack of training coming into the event.
"I tend to get out of the water ahead of her and then she catches up on the bike, which is probably her best discipline, and she is also a strong runner. So I need to perfect my bike and run elements."
Steadman, who is one of BBC Sport's Paralympic Ones to Watch for 2014, has just completed a degree in psychology at the University of Portsmouth and is a recent convert to para-triathlon.
She represented Great Britain in swimming at the Beijing and London Paralympics before opting for the sport which will make its Games debut in Rio.
She competes in the Tri4 category for athletes with arm impairments, along with fellow Britons McClelland, 35, and another former Paralympic swimmer Clare Cunningham, 36, who won the world title in 2009. She knows that she faces difficult competition from her rivals.
"When I was a swimmer, my category (S9) was very tough and to go to major events you had to beat the best in the country, who were also the top in the world," she explained.
"It is the same with para-triathlon so as long as I am up there with Faye and Clare, I know I am up there with the best in the world.
"I like a challenge and I wouldn't be doing a sport that is easy to do."
While Steadman had just one discipline to deal with in her former sporting career, she now has to master three as well as the transitions from the 750m swim to the 20km bike ride and the 5km swim.
"I have a handler, usually my dad, working with me in the transition zone but learning the best routine and what works best was a bit challenging at first," she admitted.
"I have to change out of my wetsuit, attach my prosthetic arm and put on my shoes and helmet for the cycling and then change my shoes and remove the arm for the running.
"Now I have it down to a tee and the only issue I have is with the clasp of my cycling helmet, which caused me some problems in the race in Yokohama.
"You have to find what works best for you. I've looked into having a lighter arm made but at the moment I am confident with the way it feels and with the bike set up.
"It has taken me time to get used to the bike, which is very light and has been specially adapted for me with the brakes on the left-hand side and my confidence has gone from strength to strength."
And Steadman, who has recently started working with coach Trevor Payne in Portsmouth, is hoping to gain as much race experience as she can before Rio and get the most out of Saturday's competition on home soil.
"I can't think of a better place to race than London," she admitted. "I've raced the Hyde Park course three times now so I know it very well. The crowd get behind you and gives you a sense of resilience.
"After London, I will be hoping to retain my European Championship title in Austria in June but the World Championships in August in Canada will be a big event for me.
"With trying to finish my degree, I didn't know how my fitness would be early in the season and I knew the fitness would definitely be there later on."