Senegal became the first team to record victory in the day-old Africa Cup of Nations after beating Tunisia in Group B, ending the string of draws in the first 3 games of the tournament.
Tunisia almost took the lead in the opening two minutes, but Ahmed Akaichi's header skimmed the post and he smashed a shot narrowly wide.
In between, Senegal took the lead through Sadio Mane's penalty after Cheikhou Kouyate had been hacked down.
Kara Mbodj powerfully headed in a second, and almost scored an own goal when his clearance struck the post.
Tunisia were guilty of missing plenty of chances, in particular Youssef Msakni, who headed wide from two yards out and shot straight at Abdoulaye Diallo in the second half.
Victory for Aliou Cisse's side means they top their group after Algeria's surprising 2-2 draw against Zimbabwe.
Tunisia have won the tournament once, in 2004, but Senegal have never lifted the crown. Their best performance came in 2002 when they lost on penalties to Cameroon.
This year could be a different story with a side containing Napoli centre-back Kalidou Koulibaly, West Ham's Kouyate and Everton's Idrissa Gueye in midfielder, as well as Liverpool's Mane.
Africa's most expensive player - following his £34m move from Southampton to the Reds in the summer - caused the Tunisian backline problems with his pace and coolly tucked his spot-kick into the left corner.
Senegal could have had another, but Ismaila Sarr's cross came back off the bar in the second half.