Guinea left-back Issiaga Sylla scored a first-half goal to steer his side to a 1-0 victory over depleted Malawi in Africa Cup of Nations Group B.
Malawi, making a third appearance at the finals and first since 2010, had 13 members of their squad unavailable following a Covid-19 outbreak in their camp, which meant they could only name four players on the bench that included two goalkeepers.
But they missed numerous chances to claim something from the game and were left to rue their wastefulness in front of goal after 35 minutes when Guinea forward Jose Kante slid a perfect pass through for Sylla to score from close range.
The win sees Guinea move level with Senegal at the top of the group after the latter beat Zimbabwe 1-0 in their opener thanks to a 97th minute Sadio Mane penalty earlier on Monday.
The top two will meet in their second pool game at the same venue on Friday.