Turkey beat Iran 2-1 in an international friendly at the Fatih Terim Stadium, Istanbul, Turkey on Monday.
A source close to Soyuncu informed Turkish-Football that two Arsenal officials attended the game.
There were several scouts in attendance, including Atletico Madrid who have also been linked with the centre-back.
The defender’s agent Mustafa Dogru was also present at the match.
The 22-year-old put on an impressive display, making the highest number of tackles for his side.
See More: 3 Reasons £35m Arsenal Target Caglar Soyuncu Would Be A Success At The Emirates
Soyuncu passed well and helped break out of defence with bursting forward runs, catching Iran on the counter-attack several times through the game.
Turkey did not defend well on the night and it was left to the Freiburg man to pick up the pieces.
The 22-year-old had to show leadership skills and maturity dealing with his team-mates errors.
Turkey almost kept a clean sheet until Omer Bayram decided to do a Suarez and save the ball off the line with his hand, forcing a penalty, which Iran converted just before full-time.
Everton striker Cenk Tosun scored both goals for Turkey.
The Crescent-Stars take on Tunisia next followed by World Cup 2018 hosts Russia, Soyuncu is expected to feature in the next two games as well.
Freiburg value their star man as being worth £35 million according to the Telegraph.