The backrow of the scrum is made up of 3 loose forwards, each with specific goals relating to responsibilities at the breakdown, rucks and ball-carrying duties. They are called loose forwards as they are loosely bound to the scrum and make up the numbers 6, 7 and 8 on the team sheet.
The no. 6 is called the Blindside Flanker. He is on the opposite side of the scrum to the feed, resulting in him being 'blind' or not able to see the feed going into the scrum. The 'blindside' of the scrum is also called the 'narrow' side as it is closer to the sideline than the 'openside'.
Roles within the team
The Blindside Flanker has many roles within the team and is generally the most defensive in nature of the 3 backrow forwards but not always. His main job is to make sure that the opposition team's main ball-carriers do not get over the gain-line or are smashed back before they get to the gain-line, and to keep the opposition's scrum-half quiet. As a result of this they will usually have one of the leading tackle counts at the end of a match. In the modern game and especially at professional level, Blindside Flankers have become more important offensively, being used more and more as ball-carriers to punch holes in the oppositions defence.
At the breakdown one of his prime roles, along with the Openside Flanker, is to be quick to each breakdown, to help retain or win possession before a ruck is called. After a ruck is called they still have a role to play in 'hitting' the ruck if the other team is in possession, to make it as difficult as possible for the opposition to start another phase of play.
Blindside Flankers are generally very athletic players, combining the strength to hit everything that moves, along with the speed to get around to each ruck and make every tackle.
Some of the best Blindside Flankers include Jerome Kaino of New Zealand, Schalk Burger of South Africa, Sean O'Brien of Ireland and Tom Coft of England.