TORONTO — There were no hints of nerves or awe, no indication that the first NBA Finals game in franchise history was weighing on the minds of the Toronto Raptors.

The hosts forcefully introduced themselves to the Golden State Warriors on Thursday, launching a barrage of early 3-pointers and cranking up the defensive pressure against Stephen Curry. By night’s end, the Raptors had claimed a dream opener, dictating the action throughout to defeat the defending champions, 118-109.

For the first time since Kevin Durant was lost to injury in the second round of the playoffs, the Warriors looked like an incomplete team. Toronto’s half-court defense smothered Golden State’s offense, hanging tight with Curry, denying clean looks at the rim and forcing 10 first-half turnovers. Center DeMarcus Cousins returned to the lineup after missing the previous two rounds with a leg injury, but he struggled to move defensively and scored just three points.

After a Western Conference finals in which they enjoyed oceans of space and played at light speed, the Warriors labored through half-court possessions and never got out much in the open court. Raptors Coach Nick Nurse promised that his pregame speech would be centered on transition defense, and his words landed. The Warriors managed just 17 fast-break points, many coming in a futile late flourish, and never seized control of the game flow.

Curry did his best to force the issue, scoring a game-high 34 points and getting to the foul line 14 times, but the balance around him was lacking. Only three Golden State players scored in double figures — Curry, Klay Thompson and Draymond Green — as Toronto’s scrambling help defenders did well to cover for each other.

Toronto enjoyed an energy advantage all night.

Raptors fans delighted in heckling ESPN analyst Paul Pierce, a former nemesis, and cheered enthusiastically as the franchise’s former stars, including Tracy McGrady and Damon Stoudamire, were acknowledged before the game. Sensing their opportunity, the Raptors launched eight of their first nine shots from beyond the arc, making it clear from the start that they had no plans to engage in a feeling-out process with their opponents.

Die-hards in full-body dinosaur costumes roamed the arena’s exterior, and the rowdies inside repeatedly exploded in appreciation for Pascal Siakam, who led the Raptors with 32 points and eight rebounds. The crowd reached deafening levels in the game’s final minutes, as Kyle Lowry hit a dagger 3-pointer to finish off the win.

Starting out a series on the right foot is critical for any underdog, but especially this one. The Raptors, after all, must contend with the possibility of a Durant return and with Kawhi Leonard’s uncertain health. Leonard, the driving force of Toronto’s postseason offense, finished with 23 points but shot just 5 of 14 from the field and seemed to be limited, at times, in his explosiveness and top-end speed.

Center Marc Gasol stepped up to compensate, scoring 20 points and holding his own defensively on Curry away from the basket. Fred VanVleet added 15 points off Toronto’s bench and diligently chased Curry through screens.