El Khadra are yet to concede a goal at the tournament.
Riyad Mahrez scored a wonderful goal as Algeria underlined their status as one of the favourites for the Africa Cup of Nations with a 3-0 win over Guinea which booked their place in the quarter-finals.
The Manchester City winger’s superb control and composed finish in the 57th minute put his side two goals up after Youcef Belaili’s 24th-minute opener in Cairo.
And Algeria sealed their progression as substitute Adam Ounas added a late third.
Djamel Belmadi’s side had cruised through group stages without dropping a point or conceding a goal and they were untroubled as they set up a last-eight meeting with Mali or Ivory Coast.
Belaili set them on their way, bursting into the area from the left and sliding a low finish into the far corner from a tight angle.
Mahrez’s goal was the pick of the bunch as Ismael Bennacer’s deep cross from the left picked him out on the far edge of the area.
The Premier League star’s superb first touch took him past his marker and into the area and with his second he fired a low left-footed shot into the corner.
Guinea, without key player Naby Keita because of a thigh injury, had no answer and their hopes were killed off in the 82nd minute following a swift Algeria break.
Ounas had only been on the pitch five minutes when he turned home Youcef Atal’s low ball into the area for Algeria’s third.