Within minutes, their shirts -- and those of their Togolese opponents -- were soaked through, as the humidity also appeared to stifle any creativity on the pitch.
Chances of any real note were scarce, as the 2015 champion was held to a 0-0 draw by its less illustrious opponent.
In a lackluster opening 45 minutes, Wilfried Zaha -- who swapped allegiances from England to the Ivory Coast just in time for the tournament -- was the liveliest player on the pitch on his competitive debut.
The Crystal Palace winger wriggled free of Djene Dakonam's clutches and fizzed a low cross into the box, but Jonathan Kodjia's outstretched leg missed the ball by centimeters.
The 20,500 capacity Stade d'Oyem was less than half full but what the crowd lacked in numbers, it made up for in noise and color.
Appearing in his first AFCON, Aston Villa's Kodjia drew the loudest gasp from the fans in the opening half but could only poke his effort straight at Togo's evergreen keeper Kossi Agassa.
Despite the Ivory Coast enjoying the majority of possession, Togo always looked dangerous on the counter.
Captain and talisman Emmanuel Adebayor -- without a competitive match since May 2016 -- dropped deep in the early stages in an attempt to dictate play, and a series of flicks and intricate touches continued to trouble the Ivorian defense.
With the retirement of the Kolo and Yaya Toure, much has been made of young midfielder Franck Kessie's potential to fill the considerable void left by the latter.
While the 20-year-old Atalanta star provided a reliable outlet and maintained a keen eye for a pass, he was unable to truly leave his mark on the contest.
Ivory Coast boss Michael Dussuyer then made the surprising decision to haul Zaha off with 20 minutes still to play.
As the clock entered the final 10 minutes, Togo began to sit back with veteran coach Claude Le Roy -- now in his ninth AFCON -- seemingly content with a draw.
The Ivory Coast would create one last chance, arguably the best of the match.
Max Gradel found space down left wing and picked out Serge Aurier in the box, but -- without a Togo defender in sight -- the PSG full-back skewed his header wide of the far post.
In truth, that final effort was indicative of the match as a whole.
DR Congo vs. Morocco
Monday's second game saw Morocco come up against the Democratic Republic of the Congo, or the 'Atlas Lions' against the 'Leopards'.
However, in truth, this was more a clash of domesticated cats than two of Africa's most feared predators, as DR Congo edged a 1-0 win over a toothless Morocco.
There were promising signs for Morocco in an opening period of total dominance.
While DR Congo was struggling to string more than two passes together, Morocco continuously proved a threat from both open play and set pieces.
Good work on the edge of the area from Aziz Bouhaddouz allowed teammate Mbark Boussoufa time and space to curl a shot at goal, but his dipping effort crashed against the top of the crossbar.
Imposing Moroccan defender Manuel da Costa was a constant thorn in DR Congo's side, rising highest to get on the end of free kicks and corners.
When DR Congo did eventually manage to get the better of Morocco's high-tempo pressing, its first chance fell to Cedric Bakambu but he bent his effort straight into the arms of Munir.
In the absence of injured star man Yannick Bolasie, DR Congo will be looking to Villarreal's Bakambu as a source of inspiration -- and goals -- throughout AFCON 2017.
Though Morocco continued to enjoy the lion's share of possession, DR Congo grew into the game as the second half wore on, showing no signs that Friday's missed training session -- boycotted due to alleged unpaid bonuses -- was affecting the team.
In fact, it was Morocco keeper Munir who DR Congo had to thank for breaking the deadlock after 55 minutes.
Firmin Mubele's cross from the left looked promising, if not threatening, but Munir got himself in a muddle at his near post and diverted the ball into the path of Junior Kabananga.
The 27-year-old adjusted his feet sharply and planted a half-volley into the bottom corner, sparking flamboyant celebrations from those on the pitch.
Morocco looked to be handed a lifeline 10 minutes before the end, as Lomalisa Mutambala capped a nightmare 15-minute cameo by earning his second yellow card for a rash tackle.
And, when DR Congo captain Gabriel Zakuani was injured landing awkwardly shortly afterward, the Leopards were left with little more than nine players on the pitch.
Morocco continued to probe for an equalizer but couldn't beat Vumi Matampi in the DR Congo goal, as the keeper pulled off two late reaction saves to keep his side in the lead.
The result extends DR Congo's unbeaten run over Morocco to five matches, putting it top of Group C with three points.
Morocco, meanwhile, goes bottom after the earlier draw between the Ivory Coast and Togo.