Dozens of Lens supporters stormed the Stade Bollaert-Delelis pitch on Saturday to confront the visiting Lille fans stationed in a corner of the ground after tensions flared with other spectators.
Messi outshone his teammates in PSG's all-star attack for much of the game at the Parc des Princes but he had been - slightly controversially - taken off by the time substitute Icardi headed in a cross from the left to secure the win.
PSG's fans are set for their first glimpse of Messi at home after his summer arrival from Barcelona. Messi came close to his first goal when he hit the crossbar against Brugge.
Poland midfielder Przemyslaw Frankowski scored the winning goal on 74 minutes as Lens climbed up to second in Ligue 1, unbeaten through six games and three points adrift of Paris Saint-Germain, who host Lyon on Sunday.
Manchester City have scored at least five goals in each of their last four home games in all competitions. Next in the firing line at Etihad Stadium is Southampton
PSG have come under heavy criticism after a 1-1 draw against Club Brugge in the Champions League.
Verratti will also miss the weekend Ligue 1 outing against Lyon and possibly PSG's second Champions League run out against Manchester City on 28 September.
Italy's European Championship star goalkeeper, Gianluigi Donnarumma, made his debut in goal for PSG, whose home fans must wait a while longer to see Lionel Messi at Parc des Princes.
The loss left Lille in 10th place ahead of hosting German Bundesliga highflyers Wolfsburg in their Champions League opener next week.
After 10 successful years at Bayern Munich, the 33-year-old defender joined French Ligue 1 side Lyon last week on a free transfer, but is due to return to Munich to face the allegations in court.
Midfield prodigy Camavinga, who is just 18, penned a six-year deal at the Santiago Bernabeu with Real reportedly paying a fee of 31 million euros ($36.6m) plus nine million euros more in bonuses.
Messi, wearing the number 30 jersey, came off the bench in the 66th minute to replace Neymar at the Stade Auguste-Delaune, where fans in the sell-out 21,000 crowd had earlier chanted his name as he emerged to warm up.
On loan from Arsenal, Matteo Guendouzi, in the 23rd minute, and former Flamengo player Gerson, on 51 minutes, scored their first goals for Marseille.
Pochettino said the 'magic trio' — Messi, Neymar and Mbappe — "will certainly be among those named, we will see if they can play from the start of the match."
Ligue 1: French Professional Football League expresses unhappiness over players travelling for international duty
The Italian and English top flight leagues are also upset about FIFA's decision to not extend exceptions for call-ups to countries where quarantine upon re-entry is mandatory.
Ligue 1: PSG reject Real Madrid's offer for Kylian Mbappe but open to negotiate Frenchman's transfer
Madrid have not officially confirmed or denied they made an offer for the 22-year-old France star who joined PSG from Monaco in 2017.
According to outlets L'Equipe and Le Parisien, the Ligue 1 club have rejected the proposal for 22-year-old Mbappe, whose contract at the Parc de Princes expires next June.
The prefect of the Alpes-Maritimes department said the Popular South stand at the Allianz Riviera in Nice would be closed after fans threw projectiles which led to serious incidents on Sunday during the Nice-Marseille fixture.
The injury is a setback for Icardi who has netted twice in the opening three rounds of the championship.
The game had been interrupted with players leaving the field after home fans threw projectiles and invaded the pitch. Unverified photos on social media showed at least three players were injured.