The England international slotted past Nurnberg goalkeeper Christian Mathenia after seven minutes to give the Gunners an early lead.
But there are fears that Martin Odegaard might be in trouble after being forced out of the starting line-up with a knock.
The Arsenal captain was crocked in the warm-up before the match with a full diagnosis yet to come.
Fabio Vieira took his spot in the starting XI instead while Gabriel took the captain's armband.
Saka's goal showed that the Arsenal ace is still in top form, pulling off a fine finish.
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And he did so in vintage style, collecting the ball on the right-hand side before cutting in.
Before the defender could get anywhere near him, the 22-year-old unleashed a powerful shot that hit the bottom corner of the goal.
It is a goal that Arsenal fans are becoming accustomed to, after a brilliant season last year.
Saka did not miss a single match in the Premier League last season, scoring 14 and assisting 11 in the process.
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Mikel Arteta counts on the youngster as one of his main players and is arguably the first name on the teamsheet.
However, the bad news is Odegaard's potential injury while not many details have been released yet.
The former Real Madrid star is another that Arteta counts as one of his most important players.
He missed just one Premier League match last season, scoring 15 and assisting seven in a remarkable campaign.
However, with plenty of time left before the new campaign gets underway, Arsenal will hope that the problem is just minor.
The Gunners are busy this summer and will play the MLS All-Star team on July 20 before taking on Manchester United just two days after.
Catch the latest updates from Nurnberg vs Arsenal on our live blog.