Johnson started playing rugby with the Oxfordshire based amateur club Chinnor then plying their trade in South West Division 1.
[3][4] Johnson switched to Coventry the following season and along the way to becoming the first Reading player to excel on the professional stage since Ayoola Erinle, then a future England centre.
During his Coventry days he scored an 80-metre try against Otley, this was an early indication of his nimble footwork for a big man and ability to finish moves from long range.
[8] Johnson made numerous starts for the England Saxons squad receiving many positive reviews and was part of the team that won the 2011 Churchill Cup defeating Canada in the final.
[11] Johnson was originally selected in Englands squad for the 2013 Six Nations[12] however he was dropped after suffering a knee ligament injury for Exeter Chiefs in their Heineken Cup match against Leinster at Sandy Park ruling him out of the Tournament.