Alexandre Lacazette made a stunning start to his Arsenal career by scoring on his debut to wrap up a 2-0 victory over Sydney FC.
The striker netted within 15 minutes of coming off the substitutes' bench late on at a sold-out ANZ Stadium to mark his arrival for a club-record fee in style.
It had looked until that point that a fourth-minute strike from Per Mertesacker, magnificent during the FA Cup final in his last Gunners appearance, would be the only goal of the game.
Danny Welbeck had a controversial second-half penalty saved by Sydney goalkeeper Andrew Redmayne, whose impressive performance ensured the match remained in the balance until Lacazette's late intervention.
The match was Arsenal's first pre-season encounter, with a friendly against Western Sydney Wanderers to follow on Saturday.
Arsene Wenger's side moved in front through an unlikely source in Mertesacker. Sydney failed to clear a Mesut Ozil corner from the right and the defender acrobatically hooked into bottom corner from five yards.
The Gunners kept the pressure on as Theo Walcott and Krystian Bielik were narrowly off target with efforts after Welbeck had been denied by a last-ditch block.
Walcott's strike was then unconvincingly kept out by Redmayne, but Sydney almost levelled against the run of play when Josh Brillante surged past Mertesacker and forced Petr Cech to keep out his low strike, Matt Simon clipping the outside of post from a tight angle on the rebound.
Arsenal responded when Walcott and Francis Coquelin attempts were kept out in a good double save from Redmayne, who was again called into action to deny Joe Willock after a superb solo run from the midfielder as the Gunners had to settle for a one-goal half-time advantage.
After the break, Walcott fired over following an excellent set-up from lively youngster Reiss Nelson, before sub keeper Emiliano Martinez had to save from Chris Zuvela at the other end.
A dipping Cohen Bramall attempt was then kept out by Redmayne, before Arsenal were awarded a questionable spot-kick.
A well-worked move led to Welbeck setting up Walcott, who looked destined to score, but Sebastian Ryall threw himself in the way to block with his back, only for the referee to point to the spot for handball.
But justice was done when Welbeck's penalty was saved by Redmayne down to his right.
Lacazette entered the fray among a host of Arsenal changes with 22 minutes remaining.
Arsenal again came close to a second when Edward Nketiah struck the post after latching on to a corner.
The Gunners finally sealed victory seven minutes from time, substitute Alex Iwobi making great ground down the right and squaring for the onrushing Lacazette to time his run and slot home with a low finish.
Martinez then kept out Aaron Calver from close range in the final moments to preserve Arsenal's clean sheet on a positive day for Wenger's men.