Following in the footsteps of a famous father - Mike Shellard, who formed part of a legendary Ponty back row unit with Chris Seldon and Tommy David - young Rhys progressed through the junior and youth ranks with his local club, Aberdare. International honours followed for Wales at under 16 and under 17 level as Rhys gained a fearsome reputation as a hard hitting flanker, his route to senior rugby guiding him into the ranks of the Warriors Academy. Playing on permit for the Abercynon senior team in division two of the Welsh leagues, whilst still only eighteen years of age, Rhys continued to impress, featuring for Wales at under 19 FIRA level in the 2004 six nations and World Cup tournaments. Whilst studying sports science at Neath College, Rhys made a number of appearances on dual registration for Pontypridd in the Premiership, filling the blindside and openside flanker berths with the same industrious commitment, before signing up on a permanent basis for the Sardis Road team at the commencement of the 2004/2005 campaign. Making a huge impact at premiership level during the 2004 / 2005 season, Rhys became a core member of the Wales under 21 squad, and was awarded professional regional status by the Blues Academy. Continuing his role as a dynamic openside flanker for both club and country, Rhys went on to captain the Wales under 21 team during the World Cup tournaments in 2006 and made his debut for the Blues in November of that year, playing against Edinburgh.