The new signing played on the right in the first half against Monaco, but looked far more dangerous in a central role after replacing the France striker.
After his 18-minute cameo against Benfica on Saturday, the Chilean started in Sunday’s 1-0 defeat to Monaco in the Emirates Cup and gave a glimpse of what we can expect in the 74 minutes he played before being substituted.
The result almost seemed immaterial to Arsenal supporters, many of whom turned up exclusively to see Sanchez in action. On the walk to the stadium before kickoff, every other replica shirt bared the name of the 40 million euro summer signing from Barcelona.
A huge roar greeted his name when the team lineups were announced and his arrival has sparked a surge of optimism in North London that Arsenal can mount a genuine title challenge this season.
MORE: Biggest summer transfers | Soccer's beautiful fans
Arsene Wenger believes Sanchez can be the superstar of this Arsenal team in the mould of the likes of Thierry Henry and Robin van Persie before him, and the team’s attack this season will be built around getting the most out of the marquee signing.
The Arsenal manager converted Henry and Van Persie from wingers to central strikers and his use of Sanchez on Sunday would suggest he has similar plans for his new forward.
Sanchez played the first half supporting Olivier Giroud on the right of a front three before moving into a central role after the break.
The evidence so far — and admittedly there is little to go on — suggests the 25-year-old should play down the middle instead of Giroud if Arsenal has serious trophy ambitions.
For the fast, high-tempo style that Wenger wants to play, Giroud is too static and too profligate in front of goal. Wenger said his compatriot’s poor performance against Monaco was because he was "not ready" physically, which meant he spent the first half off the pace or offside before being withdrawn at halftime.
Giroud simply isn’t the top-quality forward needed as the spearhead in a title-winning team.
But Sanchez is. He scored 21 goals for Barcelona last season and provided 15 assists in all competitions. With Mesut Ozil, Theo Walcott, Alex Oxlade-Chamberlain and Santi Cazorla around him, he can thrive in a central position and replicate Van Persie’s 30-goal campaign in 2011-12.
In the first half here, Sanchez’s contribution was limited in a wide position, particularly with Giroud failing to provide the movement and link-up play to produce fluid attacks.
While Sanchez could stomach playing a support role for Lionel Messi at Barcelona, he won't feel quite so accommodating about the prospect of doing the same for Giroud in North London.
In the second period, he played on the shoulder of the last man, constantly looking to break in behind the Monaco defense with a burst of speed and clever movement.
His running in the channels stretched the game, allowing him to show his technical skills and trickery to link up with teammates, speeding up Arsenal's play as it looked to zip the ball around.
Sanchez should have marked his first start for Arsenal with a goal but he tightened up and sliced wide from 12 yards when the ball rolled invitingly to him in the penalty area.
At the other end, Radamel Falcao showed the value of a lethal finisher and his first-half header proved to be the winner for the Ligue 1 side, denying Arsenal the Emirates Cup trophy.
Sanchez is a very different style of player, but he can be just as ruthless if deployed as the spearhead of the Arsenal attack.