USGN had booked their place in the second preliminary round of the Champions League after beating Le Messager Ngozi of Burundi 2-1 on aggregate in the first round last month.
On Saturday, the Niger side piled pressure on title holders Ahly in the second half of the game, scoring the draw goal with 15 minutes left on the clock.
"Ahly played a good game in the first half but we played well in the second half. We missed many scoring chances but we finally scored the draw," USGN coach Zakari Yao Ibrahim said.
Tunisian full-back Ali Maaloul dispatched a 19th-minute penalty to put Ahly in front but USGN secured a draw with a second-half goal at the General Seyni Kountche stadium in Niamey.
"Before the game we were not familiar with Ahly's tactics so they managed to take the upper hand in the first half but we dominated them in the remaining 70 minutes."
"Now that we watched Ahly's tactics in a full game and we discussed them well and discovered their weakness points, we will count on it in the 2nd leg game to qualify for the next round," Ibrahim added.
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