The two teams will be looking to make a winning start to life in Group A that also includes Faroe Island minnows KI Klaksvik and Slovakian club Slovan Bratislava.
Match preview
After a year away from European football, Lille managed to scrape through to the group stage of this season's Conference League courtesy of a 3-2 aggregate win over Rejika in the playoff round, with Jonathan David netting the decisive goal in extra-time of the second leg.
Les Dogues are yet to set the world alight with their performances so far this season, picking up eight points from their opening five Ligue 1 fixtures, and they let a two-goal lead slip in their most recent match to draw 2-2 away against Rennes last weekend.
Paulo Fonseca's side were boasting a two-goal lead heading into the final 15 minutes thanks to strikes from Leny Yoro and Bafode Diakite, but Rennes fought back with goals from Lorenz Assignon and Ibrahim Salah, the latter of whom netting an 89th-minute equaliser, to force both sides to share the spoils.
Fonseca felt that his team "didn't deserve" to drop points after a strong showing against Rennes, and the 50-year-old has insisted that he has "confidence for the future" heading into a busy fixture schedule in all competitions.
Lille, who were competing in the Champions League last 16 just two years ago, will be confident of success against Olimpija on Wednesday as they have put together an impressive 21-game unbeaten run at the Stade Pierre-Mauroy, winning 17 of those matches and scoring at least two goals on 15 occasions in the process.
Olimpija's hopes of ending Lille's unbeaten home streak are slim considering the Slovenian side have already suffered disappointing results in European competition this term, losing in both the Champions League and Europa League qualifiers against Galatasaray and Qarabag respectively.
Nevertheless, Olimpija can now look forward to their first-ever Conference League group-stage campaign in a relatively open Group A with Lille, KI Klaksvik and Slovan Bratislava, and will be hoping to take their solid domestic form onto the continent.
Indeed, the reigning Slovenian PrvaLiga champions have won five of their opening seven games of the new season and have scored a league-high 20 goals, netting twice in last weekend's 2-1 home victory over Maribor.
Joao Henriques's men will welcome the challenge of facing Lille on Wednesday, but they must rectify their away form if they wish to claim a positive result in France, as they have failed to win 10 of their 16 competitive away fixtures in all competitions since the turn of the year.
Lille Europa Conference League form:
W
D
Lille form (all competitions):
W
W
L
D
W
D
NK Olimpija Ljubljana form (all competitions):
W
L
L
D
W
W
Advert - content below:
Team News
Lille winger Adam Ounas has not represented the French side since sustaining a muscle injury in the first leg of their Conference League playoff last month, and the Algerian is set to remain on the sidelines along with defender Tiago Djalo (knee), while midfielder Nabil Bentaleb (calf) is doubtful.
After scoring at the weekend, Diakite could keep his place at right-back, which would likely see summer signing Samuel Umtiti continue to link arms in central defence with 17-year-old rising star Leny Yoro.
Fonseca is unlikely to make too many changes, if any, to his attack with Yusuf Yazici, Remy Cabella and Ivan Cavaleiro all set to provide support for central striker Jonathan David.
As for Olimpija, captain Timi Elsnik missed the win over Maribor due to injury and is a doubt for Wednesday's contest, so Ivan Posavec could continue alongside Agustin Doffo and Diogo Pinto in centre-midfield.
At the age of just 19, Marcel Ratnik became Olimpija's youngest-ever captain against Maribor in the absence of Elsnik, and the centre-back may wear the armband again against Lille, joining Jorge Silva, Ahmet Muhamedbegovic and David Sualehe in the back four.
Portuguese forward Rui Pedro has scored seven goals in 15 games across all tournaments so far this season and he is set to continue in the front three alongside Pedro Lucas and Nemanja Motika.
Lille possible starting lineup:
Chevalier; Diakite, Yoro, Umtiti, Ismaily; Andre, Gomes; Yazici, Cabella, Cavaleiro; David
NK Olimpija Ljubljana possible starting lineup:
Vidovsek; Silva, Ratnik, Muhamedbegovic, Sualehe; Posavec, Doffo, Pinto; Pedro, Lucas, Motika