As the two sides lined up to passionately sing their respective national anthems in the de jure capital of Yamoussoukro, cameras panned to supporters of both sides who eagerly awaited kick-off with the lively chants they're so well-known for.
After the 1-1 draw against Guinea in the first group game, Cameroon manager Rigobert Song changed his line-up drastically, making five changes including the introduction of Manchester United goalkeeper, Andre Onana after a late arrival to the tournament.
Aliou Cisse's side only made one change on the other hand, with Tottenham's Pape Sarr coming in for Moussa Niakhite. Sarr's start saw him take Abdou Diallo's role in the centre of the park, often slotting between the two centre backs to form a back five.
Cameroon started off strongly, trying to prevent a Senegal win that would see them guarantee qualification to the next round.
Unfortunately their efforts were not enough, as Ismaila Sarr scored the first goal of the game in the 16th minute to make it 1-0 to the reigning Africa Cup of Nations champions.
As a cross came into the Cameroon box, Onana's punch ended up at Sarr's feet inside the area, who's shot deflected off Andre-Frank Zambo Anguissa, wrongfooting the keeper and ending up in the bottom right corner.
Senegal proceeded to let the Indomitable Lions pass the ball around in the middle of the park, setting up in a mid-block with the midfield three sitting very close to the backline, forcing Cameroon to play it wide.
When they eventually won the ball back in the 21st minute they transitioned well, leading to a four against two on the counter attack. The promising chance was then wasted by Lamine Camara as the 20-year-old overhit his through ball to Habibou Diallo.
Song's side struggled to get out of their own half after the cooling break, with Onana's attempts at playing long balls ending up at Edouard Mendy's feet.
In the 38th minute, talisman Sadio Mane had a chance to double the lead, but his left-footed shot was saved after being slipped through on goal by Camara.
As half-time approached, Cameroon upped the pace a little with a bit more intent on the ball. It failed to threaten their opponents though, who pressed well high up the pitch until the whistle went.
Half-Time: Senegal 1-0 Cameroon
Cameroon started the second half well, holding possession and winning it back quickly when they lost it.
The Teranga Lions fans started to roar after their side started to dart the ball around the pitch, evading the Cameroon press and eventually leading to an entry to the opposition box in the 55th minute, cleaned up well with a sliding challenge from Nouhou Tolo that Nemanja Vidic would be proud of.
Abdou Diallo picked up a seemingly harsh yellow card that means he will now miss the next game against Guinea, posing Aliou Cisse a problem now that Niakhite is injured.
What was a relatively disciplined game became a little scrappy as the 60 minute mark approached with both sides wrestling for control.
Cameroon followed up with a flurry of set pieces, but very few of the crosses into the box found green shirts.
The Teranga Lions started to dominate the Indomitable as the game went on. After some intricate play around the box, Ismaila Sarr put a pass across the face of the goal that found a sliding Habibou Diallo at the back post, making it 2-0.
Cameroon finally made their first substitute of the game, sending Faris Moumbagna on for Nicolas Ngamaleu on the right wing.
Senegal responded by sending Idrissa Gana Gueye on for Pape Sarr after a strong performance the Tottenham midfielder can be proud of.
Yvan Noupa showed his side's frustration after a bad challenge on Ismaila Sarr that gave his team a chance to catch their breath as the Marseille man received treatment.
Senegal weren't finished there, bringing on fresh legs and a set of attacking players with Nicolas Jackson and Iliman Ndiaye coming on.
In the 83rd minute, Cameroon, who seemed defeated, finally scored from one of the corners sent into the box, with Jean-Charles Castalletto heading home a cross from Olivier Ntcham to give his side the hope of a comeback.
Georges-Kevin N'Koudou nearly found the equaliser for his side, making an intelligent run at the back post to a cross-field pass that was slightly too far ahead of him.
With seven minutes added time, Cisse's team looked to hold on against the bombardment of long balls into their half, and did so well.
Nkoudou appeared again at the back posst in the 93rd minute after a perfect ball in from Castelletto, but it was painfully headed wide from a matter of yards away from the goal.
Sadio Mane made sure Cameroon's hopes lasted no longer though. A pass to the left wing found Gueye, who put a cross in similar to Sarr's for the second goal that was guided into the bottom left corner by Al Nassr winger.
Full Time: Senegal 3-1 Cameroon
Senegal now sit on top of the Group C table on six points and are through to the next round. Cameroon will be hoping that the Guinea vs Gambia game later tonight goes their way as they hope to avoid a disappointing tournament.
In the end, the three points by Senegal seemed deserved, and Cameroon will need to show more of the fighting spirit we saw in the last 10 minutes if they hope to qualify for the next round.
