When Senegal took the lead through Ismaila Sarr, a former Watford player, the Manchester United goalkeeper had a terrible start for his nation.
Cameroon, who were trying to get back into the game, were awarded a free-kιck in the middle of the second half by Onana’s team.
Pathe Ciss had the ball set up 35 yards out from goal when the quirky goalie appeared from behind him to provide some advice on the next set piece.
Even though Onana ran nearly the whole length of the field to deliver some crucial advise, Ciss’s free-kιck went right out of play, setting up a goal kιck.
Habib Diallo put Cameroon up 2-0, and things didn’t get much better until seven minutes before the end of the game, when Jean-Charles Castelletto scored a goal to pull one back.
Sadio Mane, a former Liverpool star, scored in ιnjury time to give Senegal a vital 3-1 victory and end the game.
With just one point from their first two matches, Onana and Cameroon will now face Gambia in a pivotal deciding match on Tuesday after suffering that loss.
After a harrowing ordeal, Onana’s plane landed 100 miles away from his teammates, causing him to miss Cameroon’s AFCON opener.
This followed a quick exit following Manchester United’s 2-2 tie with Tottenham.