|New South Wales (4) 4|
|Queensland (6) 6|
|Try: Gagai Goal: Thurston|
Holders Queensland began their 2016 State of Origin defence with a two-point victory against New South Wales in the Sydney opener.
Johnathan Thurston's penalty was overhauled by Boyd Cordner's score but Dane Gagai finished on the right to give the Maroons a half-time lead.
The second half was an arm-wrestle, typified by forward graft and grunt.
Blues' Josh Morris crossed, only for the try to be ruled out as neither side scored points after half-time.
Victory was particularly sweet for captain Cameron Smith, who appeared in his 37th Origin game to pass former team-mate Darren Lockyer as record appearance maker.
Queensland can seal the 2016 series at Suncorp in Brisbane on 22 June, with the return to ANZ Stadium on 13 July.
History is on their side, as 25 of the past 34 series have been won by the winner of the opening game.
Although not quite as tight as 1995's 2-0 Queensland win, the scoreline reflected the desperation of both sides not to concede in this Origin opener, and neither truly sparkled despite periods of pressure.
Queensland and Thurston took a penalty shot early on to put them ahead after failing to breach the Blues, whose indiscipline gave them early defensive work to do.
However the Blues' smart kicking built up pressure in attack that told when James Maloney's short-ball put Cordner through to score the opening try.
Smart hands by the Maroons out wide worked Gagai in for his second in as many appearances before half-time and only brilliant cover defence stopped the Newcastle winger from adding a third after the break.
Desperate scrambling defence at both ends, notably to snuff out teasing kicks, maintained the two-point gap.
New South Wales: Moylan; Ferguson, Jennings, Morris, Mansour; Maloney, Reynolds; Woods, Farah, Gallen, Cordner, Jackson, Bird.
Replacements: Walker, Tamou, Klemmer, Fifita.
Queensland: Boyd; Oates, Inglis, O'Neill, Gagai; Thurston, Cronk; Scott, Smith, Myles, Gillett, Thaiday, Parker.
Replacements: Morgan, McGuire, Guerra, Papalii.
Referee: Ashley Klein (Australia)
Subscribe to the BBC Sport newsletter to get our pick of news, features and video sent to your inbox.