Having started with Swansea, the young openside will join the Dragons in June.
On signing the fresh new talent, Dragons Director of Rugby Lyn Jones said, “I have always been a big fan of Sam and his brother before him.
“He comes from a good rugby family and has the edge to become a quality international player. Playing regularly will help him achieve his ambitions.
“This is a significant signing for us and just shows our determination to become the best region in Wales.”
