From the obvious to the subtle, what are the differences between rugby union's two major formats?

How are the laws of sevens different to XVs?

Sevens is a fast, try-laden and aerobically-gruelling variation of rugby union.

The core laws of the format are the same as rugby XVs, but there are several tweaks to the lawbook that allow sevens to exploit its unique characteristics.

Let’s start extremely simple. Sevens is a seven-a-side version of rugby while XVs has, you guessed it, 15 players per side.

Both are played on a full-size pitch, but halves last for seven minutes rather than XVs’ 40. That is still plenty of time to work up a sweat with so much space to cover.

There are three forwards and four backs in sevens, compared to eight and seven respectively in XVs. The fast-flowing, expansive nature of sevens means positions are rather fluid.

International sevens teams can use up to five replacements, three less than in XVs.

The scoring system is identical to XVs, though penalty kicks are very rare in sevens except at the end of a half. Drop goals are even more unusual.

Conversions and penalty attempts are drop-kicks rather than off a tee.

Scrums involve only three players per team in sevens, compared to eight in XVs. As a result, the sevens set-piece yields much less force and XVs rules preventing contested scrums when a registered front-rower is sent off or injured do not apply.

A yellow card results in a two-minute sin bin, rather than ten.

For restarts, the team who scored the try kicks off in sevens, unlike in XVs. This is because the value of possession compared to field position is much higher with fewer players.

Sevens has its own World Cup that involves concurrent men’s and women’s events, and will be held in 2022. The World Sevens Series is an annual league comprised of several group and knockout tournaments.

The format is also played at the Olympics and will continue to be part of the Commonwealth Games at Birmingham 2022.

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