The road to success all began for Melissa at the age of 11 years old when she first started athletics, contesting most events and quickly excelling in the 800m, reaching state level. Proving her abilities weren't confined to steeplechase, Melissa placed an outstanding eighth in the 1500m at the World Junior Championships in Santiago, Chile in October and then, in March 2001, placed 14th in the World Junior Cross Country Championships.
During mid 2010, Melissa's bid for the Delhi Commonwealth Games was derailed due to injury. It was at this point, while cross-training on the bike that she made the decision to change focus from running to triathlon. In the months that followed, Melissa enjoyed a stunning start to her triathlon career with numerous wins and a handful of course records within the space of a few months.
In 2011, she made a full-time, dedicated switch to triathlon and went on to be undefeated in her first full year in the Sport. In the process she broke numerous course records and won a handful of major races around the world including the 70.3 World Championships, the 70.3 Asia-Pacific Championships and the shorter Olympic distance Noosa Triathlon. For her achievements, Melissa was awarded Female Triathlete of the year at Triathlon Australia's annual awards banquet. 2012 brought continued success with a further 9 podium finishes, 5 wins, 3 more course records and the Australian 70.3 Championship title. The 2012 season was however soured by a 4th place finish at the IM 70.3 World Championships due to illness the week of the race. She came back from this setback to finish the year with a series of wins in Augusta, Mandurah, and Phuket. Then continued into early 2013 with a win at the Australian Long Course Championships and the prestigious Abu Dhabi International Triathlon.
Melissa's achievements for 2013 earned her the title of Female Triathlete of the Year by Triathlete Magazine. Ironman.com awarded her with Performance of the Year.