This opinion was supported by previous World Rugby research yet it was still rated in rugby among the top five most frequently occurring match injuries in the 2009 to 2010 season2 .
Previous World Rugby research concluded that concussion was underrecognised1 .
This opinion was supported by previous World Rugby research , which concluded that concussion was underrecognised1 , yet it was still rated in rugby among the top five most frequently occurring match injuries in the 2009 to 2010 season2 .