Algeria began the defence of their Africa Cup of Nations title with a goalless draw against a stubborn and spirited Sierra Leone side in Group E.
The Leone Stars had the better first-half openings, with Alhaji Kamara sending two chances narrowly wide.
After the break Algeria forward Yacine Brahimi shot straight at keeper Mohamed Nbalie Kamara, who also tipped a low shot from Riyad Mahrez past the post.
Nbalie Kamara denied Ramy Bensebaini and Baghdad Bounedjah in stoppage time.
Former England defender Steven Caulker, who recently switched international allegiance to Sierra Leone, made two crucial blocks to help his side to a clean sheet on their first Nations Cup appearance since 1996.