Newly-arrived striker Mostafa Mohamed on Tuesday came from the bench to mark his Galatasaray debut with a goal as his side demolished Istanbul Basaksehir with three unanswered goals in the Turkish league.
Mohamed came as a substitute to former Barcelona midfielder Arda Turan at the start of the second half and opened his new adventure from a penalty in stoppage time.
The Egyptian international fired a powerful low shot into the bottom corner from the spot to complete the rout.
Mohamed joined Galatasaray from Egypt's Zamalek on a season-and-a-half loan contract last Thursday, with the Turkish club paying $2 million for his services with an option to make the deal permanent at the end of the year.
Galatasaray lie second in the Turkish league table with 45 points, three behind leaders Fenerbahce after 22 matches.