A guide to rugby sevens at the Olympics

HOW RUGBY SEVENS WORKS AT THE OLYMPICS:

* Both men's and women's competitions are played over three days at Deodoro Stadium

* Comprises 12 nations divided into three pools, where four teams play each other once in the group stage

* The top eight teams go through to the knockout stage where winners progress from quarter-finals and semi-finals to final

* The fast-paced games are played over seven minute halves but the final is contested over 10 minute halves

* Teams have 12 players with seven on the field at the same time and a maximum five interchanges

* Traditional rugby laws enforced on full-sized pitch with tries worth five points, conversions two and penalty and field goals three