Goalkeeper Fernando Muslera also did his part to keep Galatasaray in the game. The Uruguay international denied Angel di Maria's first chance in the second minute, swooped to take the ball from Icardi, then produced a brilliant save to deny di Maria again.
Thomas Tuchel was getting increasingly frustrated on the sideline as his side failed to make its superiority count. He received a yellow card in the 39th for protesting. Tuchel was also booked in a French league game at the weekend.
Keylor Navas dived to his right to save Jean-Michael Seri's effort from a free kick after the break, but ultimately the PSG keeper had little to do. However, Muslera again denied di Maria in a one-on-one in the 51st.
Icardi finally made the breakthrough a minute later after Marco Verratti sent Sarabia through and the Spaniard squared the ball to give the Argentine a simple finish. Tuchel brought on Kylian Mbappé for the last half hour. He too was thwarted by Muslera, but Icardi's goal was enough for PSG to maintain its winning start in Group A after opening with a 3-0 victory over Real Madrid.
Madrid narrowly avoided opening its Champions League campaign with a second consecutive defeat by salvaging a 2-2 draw at home to Club Brugge in the other group game on Tuesday.
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