File photo of Mahmoud Trezeguet (R) (the player's official Twitter account)
Trezeguet narrowed the gap on 14 minutes after Gaziantep had gone 2-0 up in the first ten minutes.
He found the bottom corner with a fine shot from inside the area, taking his tally to two league goals in the Turkish league so far this season.
Trezeguet also had hand in Trabzonspor's second goal after winning a penalty, which Tasos Bakasetas converted to level the score at 2-2 three minutes before halftime.
Former Barcelona defender Marc Bartra then scored deep in stoppage time to give Trabzonspor a precious win.
Trezeguet joined Trabzonspor from English Premier League club Aston Villa in the summer. He has scored two goals in 11 appearances with the club in all competitions so far this season.
The 27-year-old is among eight foreign-based players called-up by Egypt's new coach Rui Vitoria for two friendly games against Niger and Liberia on 23 and 27 September respectively.
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