Denayer made his first ever Champions League start but the Lions lost the game 2-0 at the Türk Telekom Arena.
Despite conceding twice Denayer was one of the few Galatasaray players to put in an impressive performance.
Denayer made several key blocks – four in total and more than any other player in the game – preventing Atleti from converting two clear goal scoring opportunities.
The 20-year-old was moved to right-back in the second half following Yasin Öztekin being brought on for Sabri Sarıoğlu.
The young defender settled in well to his new role and linked up with Öztekin to provide some of the Istanbul gains most dangerous attacking moves on the night.
Denayer made several forward runs and showed great technical ability at stages in the second half.
The Belgium international joined Galatasaray on-loan from Manchester City over the summer transfer window.
Denayer has a £30 million release clause according to Galatasaray president Dursun Özbek.
“Denayer is one of the highest value players in Turkey and has a £30 million release clause,” Özbek said speaking on the ‘Sportürk’ program on Habertürk.