The €40 million signing from Barcelona was only given a brief window to exhibit his quality as he replaced Joel Campbell with 17 minutes remaining in the second half.
Goal looks at the Chile international's highlights during the Emirates Cup victory, as well as what the season may hold...
|PERFORMANCE AGAINST BENFICA
Sanchez came on to a standing ovation in the 73rd minute and immediately took up a role on the left flank.
The Chile international's first significant involvement saw him latch onto a through ball from Santi Cazorla, but he was unable to pick out Jack Wilshere with his cross after a few step-overs.
Sanchez then moved to a central position and linked up well with Chuba Akpom during a swift Arsenal counter. Akpom exchanged passes with the Chilean but the 18-year-old was brought down by Loris Benito before he could play in his new team-mate, who was racing through the centre towards Benfica's goal.
Sanchez also showed his defensive awareness as he attempted to track back in order to stifle a Benfica attack but he fouled Nicolas Gaitan in the process.
And the former Barcelona star almost capped his fleeting run-out with an assist. After exchanging passes with Cazorla, Sanchez cut the ball back to Francis Coqulin only for the Frenchman to strike the post with his effort at goal.
|WHAT DOES THE FUTURE HOLD?|
Hopefully a large trophy haul with his new club. Arsenal may have spent 128 days at the top of the table last season but their Premier League title challenge collapsed after picking up just three wins in 11 games between January 28 and April 6.
The addition of Sanchez will add the pace Arsene Wenger has craved but, more importantly, will also boost the quality in Arsenal's attack, which should give them the staying power that was lacking last season.
In the short term, Sanchez is initially expected to adopt a wide role just off Olivier Giroud but Wenger is adamant the Chile international is capable of vying for a central position.
"He is a striker and he's a good finisher," said Wenger.
"He made a great impression in Italy [at Udinese] - I saw him there and he was really outstanding.
"I like the fact he can play left, right, up front and that's why I went for him.
"At the moment I want to see him in both positions. But I took him because he is a player who has the qualities of Walcott, he goes behind the defenders off the ball. And with the quality of his runs he can be very important for us."
|A GOOD SEASON WOULD BE...|
If it's anything like the return in his final season with Barcelona, Arsenal will be satisfied with their €40m outlay.
Sanchez scored 21 goals and registered 15 assists in all competitions last term from a supporting role on the right of Barcelona's attack. Matching that in his debut campaign for Arsenal would be a tall order, given his likely need to adapt to the Premier League, but reaching at least double figures for both goals and assists would be a respectable haul.
Arsenal will also be hoping that Sanchez can remain a force throughout the campaign. The €50m arrival of Mesut Ozil from Real Madrid last summer significantly bolstered the quality of Wenger's midfield but the Germany international was hampered by a hamstring injury in March and struggled to replicate his early-season form.
Wenger's desire to try Sanchez in a central role will also test the 25-year-old's versatility and if he can swiftly adapt to the position, Arsenal's title challenge will be enhanced.