Having won the first leg 5-0, Mazembe were overwhelming favorites ahead of the clash in Rades but fell behind to an early goal from Esperance's Ghanaian defender Harrison Afful.
The defender took a deep breath and sent his kick high into the roof of Enyeama goal, to the delight of his team-mates and the thousands of Tunisia fans at Stade Rades.
Chansa and the rest of Zambia's preliminary squad are training in Spain ahead of the tournament and will travel to play Tunisia at Rades on 6 January and they then take on Morocco six days later.