At international level, Kavanagh won his first gold medal aged 13, when he competed with Ireland at the 2003 'Four Nations' Championships.

Later that year, he won silver with Ireland in the 'Round Robin' Championships, another team competition where they fought boxers from England, France, Germany, Italy, Ukraine and Lithuania.

Fighting in the Light Welterweight category, he won silver after losing to Cuban fighter, Frank Isla in the final.

He subsequently moved to Los Angeles where he would train under Freddie Roach at the Wild Card Gym, and frequently spar with fighters such as Manny Pacquiao.

After voicing his concerns to Golden Boy, they put him in touch with Joel Díaz, who Kavanagh began training with instead.

[7] In February 2016, Kavanagh was scheduled to fight Portuguese boxer Antonio Joao Benito at the National Stadium in Ireland.

Paul, who was just two years older than Jamie, had been one of Kavanagh's first training partners after introducing him to Crumlin Boxing Club when they were young.