Teenager Gabriel Martinelli scored on his debut for Arsenal to help lift the side to a 3-0 win over the Colorado Rapids during their pre-season tour.
The 18-year-old, who was signed for £6million from Brazil’s Ituano FC on July 2, fired home a cross from Dominic Thompson in the 61st minute in Denver.
Bukayo Saka and James Olayinka’s first-half efforts had earlier put the Gunners firmly in control as they kicked off their tour of the United States.
Arsenal: Macey, Jenkinson, Chambers (Mustafi 62), Medley, Thompson (Kolasinac 64), Olayinka (Willock 62), Burton, Martinelli (Lacazette 78), John-Jules (Ozil 78), Saka, Nketiah (Aubameyang 78)
Subs not used: Leno, Sokratis, Mkhitaryan, Maitland-Niles, Monreal, Nelson, Martinez, Xhaka
Goals: Saka 13, Olayinka 29, Martinelli 61
Martinelli was in fine form from the off, just missing a chance to put himself on the scoreboard in the first five minutes when his finish went wide.
Seventeen-year-old Saka put Arsenal in the lead after 13 minutes, dinking the ball over Colorado goalkeeper Clint Irwin following impressive work from Eddie Nketiah, before Olayinka doubled the advantage 16 minutes later with a strike into the top left-hand corner.
Unai Emery had featured many of the younger players in his starting line-up, but Mesut Ozil, Pierre-Emerick Aubameyang and Alexandre Lacazette were brought on in the closing minutes.
Arsenal will continue their pre-season tour with International Champions Cup matches against Bayern Munich, Fiorentina and Real Madrid in Los Angeles, Charlotte and Washington DC respectively.