The best of three match format started in 1982, although a regular interstate match with a single clash had been played in the years before.

The combatants represent their states - NSW and Queensland, which are the undisputed power bases of rugby league in Australia.

The level of rivalry, epitomised by the 'state against state, mate against mate' slogan, invokes a passion and tribalism that arguably transcends that of the grand final in the national club championship.

In the early years, State of Origin matches invariably started with a softening up of the opposition with unduly rough physical clashes and this would then boil over into a brawl or melee.

In recent years though, this approach has given way to the more strategic tactic of sticking to the game plan.

However, the risk of a 'bit of biff' is always on the cards.

At times in the past NSW has dominated the score card but more recently Queensland had a winning streak of 8 series wins before NSW succeeded in winning the trophy back in 2014.

Queensland though, regained it last year. Over the 34 years of State of Origin the winning record has been relatively even but with Queensland dominating recent years. Queensland has won 19 series to NSW 13 with two draws.

For individual matches Queensland leads 56 over NSW's 47.

These matches have seen the making of reputations.

For Queensland, the likes of Beetson, Meninga, Lazarus, Lewis, Langer and Thurston have starred, while for NSW, Sterling, Mortimer, Clyde, Stewart, Daley and Fittler have equally risen to prominence.