As soon as Tunisia’s win over Algeria was over, the Senegal fans filed into a corner of the stadium. They had no need to wait – one ticket gets you into both parts of the double-header – but some sense of courtesy seemed to hold them back. They are, after all, by some way the noisiest fans in Group B and within seconds of turning their block of seats yellow, green and red, had set up a rhythmic drumming and whistling that they maintained until the final whistle. By then, the game had long since been won: 2-0 was no measure of Senegal’s superiority and, with better finishing, they could easily have won by two or three times that. As it is, they are through to the quarter-finals with a game to play and guaranteed to top the group.

The only lull in the Senegalese din came during the national anthem as they rhythmically patted the air in front of them, either bare-armed or with enormous inflatable orange hands. Gabon is home to thousands of expats from other west and central African nations – to the extent that a shop is known as ‘un Malien’ – and many of the local taxis sport the flags of Burkina Faso, DR Congo, Cameroon and Senegal. This wasn’t a huge crowd, but it was one that cared, local Senegalese mingling with the (semi-)official fan clubs.

They were treated to a comfortable Senegal victory. With Sadio Mané on one flank and Keita Baldé on the other, they attacked with pace, looking far more fluent than any other side up till now in the tournament (perhaps helped by the Franceville pitch, which is probably the best in Gabon). Zimbabwe, admittedly without looking defensively secure, had impressed in drawing against Algeria but they were cut apart again and again particularly in the first half-hour.

Mané touched in a low Keita cross to open the scoring after 10 minutes and Henri Saivet, once of Newcastle, bent in a free-kick to make it two four minutes later. Only a fine block from the Zimbabwe goalkeeper Tatenda Mkuruva and a follow-up header off the line from Costa Nhamoinesu prevented Mané adding what would have been his second midway through the second half.

But alongside the delight at a quarter-final place here is also expectation, and that brings pressure. Responsibility is perhaps too strong a word but this is one of the better squads in Senegal’s history and there’s no doubt Senegal feels keenly the fact that it has never won the Cup of Nations. “This is a great generation,” said the coach Aliou Cissé, once of Birmingham and Portsmouth. “What we’re changing is the mindset. It’s not just about playing a pass or some technical skill, it’s about lifting the whole level of African football. That’s our objective.”

Their performances at the 2002 World Cup, when they reached the quarter-finals, create a misleading impression: Senegal has never had sustained success as a football nation. There was a fourth-placed finish at the Cup of Nations in 1965, but that was at a time when only six nations participated.

Between 1968 and 1986 they didn’t even qualify for the Cup of Nations. Reaching the 2002 final with the team of El-Hadji Diouf, Khalilou Fadiga and Salif Diao is the best they have done.

Four of that side – Cissé, his assistant Omar Daf, the goalkeeping coach Tony Sylva and the team coordinator Lamine Diatta – now form the core of the coaching staff, while the squad once again has the balance and depth to make them serious challengers. There’s the Napoli centre-back Kalidou Koulibaly, the Everton midfielder Idrissa Gueye, the West Ham midfielder Cheikhou Kouyaté and the wingers Baldé and, most of all, Mané.

“What Mané has is a gift from God,” said Cissé. “I’m not the one who has helped to lift his level or who makes him the person he is. Of course it’s good for him to be in the team he is in at the moment [Liverpool], a team that gives him opportunities to improve, and he just needs to carry on what he’s doing.”

In terms of personality, of course, Mané is very different to Diouf, but he performs a similar function in the side. He is the player of great attacking quality, the one who can unlock a tight game or punish a moment of sloppiness from an opponent. Senegal were struggling against Tunisia in their opening game when his pass opened up the defence leading to a penalty he converted.

But he has little of Diouf’s braggadocio. He is popular and clearly no introvert, but neither is he always thrusting himself into centre stage. “We know how good our attacking players are,” said Gueye with a broad grin. “But sometimes it’s difficult because they don’t defend. If they score and we win the game, it’s not a problem, but if we lose, we will kill them.”

Mané is quietly spoken as at times to be almost inaudible. He is still the proud provincial, brought up in the village of Banbali in the rural south of Senegal. His father is the imam there and he recently paid for the reconstruction of the mosque.

Perhaps he isn’t even so gifted a player as Diouf in a purely technical sense, but what he does have is prodigious pace and a capacity to attack on the diagonal, hitting full-backs on their wrong foot, that makes him, if not unique, then certainly highly unusual. It adds significantly to Liverpool’s threat on the counter and, especially given his interaction with Baldé, gives Senegal an incisiveness no side at this Cup of Nations has yet matched.