The Rugby Football Union has announced that rolling substitutions will be introduced into the National Under-20 County Championship next season.
The extension of the experiment that was first trialled in the senior County Championship in 2010 will see each team allowed to make up to 12 interchanges per game, with players allowed to return to action having already been substituted.
The initial trial was proposed by a RFU task group in the wake of the 'Bloodgate' scandal in 2009 that saw Premiership side Harlequins fake a blood injury in order to manipulate a substitution having exhausted their regular replacements.
The International Rugby Board sanctioned the experiment and the RFU Council subsequently approved its use in the County Championship. Rolling replacements are commonplace in rugby league that allows four replacements and up to 10 interchanges.