While the Reds have already qualified for the last 16 as group winners, Union SG still have an outside chance of finishing in the top two and securing their spot in the knockout rounds.
Match preview
Competing in the Europa League for just the second time in their history, Union SG's hopes of reaching the knockout round for the second successive year are out of their hands after playing out a goalless draw with Toulouse on matchday five a fortnight ago.
Alexander Blessin's side sit third in Group E after picking up five points from as many games, and they are required to pull off a colossal upset against Liverpool in their final group fixture, as well as hope that second-placed Toulouse suffer defeat to LASK Linz, if they are to progress to the knockout rounds.
Should Union SG finish third in the group, they will drop down into the Europa Conference League playoffs, but a potential fourth-placed finish would see them crash out of Europe altogether.
Since drawing with Toulouse, Union SG have won each of their last three domestic games by an aggregate score of 7-2, including last weekend's 3-1 victory away against Charleroi, a result which helped Blessin's men move six points clear at the top of the Belgian Pro League.
The Brussels-based outfit are now bidding to win successive Europa League home games for the first time, after beating LASK Linz 2-1 in October, but defeating Liverpool could prove challenging as they have lost each of their previous three meetings with English opposition, including a 2-0 defeat against the Reds at Anfield in the reverse fixture in September.
Despite losing 3-2 to Toulouse on matchday four, Liverpool have punched their ticket to the Europa League last 16 with a game to spare after cruising to a 4-0 home victory over LASK Linz on matchday five two weeks ago.
Goals from Cody Gakpo (2), Luis Diaz and Mohamed Salah helped the Reds claim their fourth win in Group E, as well as their 10th in a row at Anfield across all competitions this season, and they are now guaranteed to top the group as they sit four points clear of Toulouse in second.
Success over LASK Linz kick-started a four-match winning run for Jurgen Klopp's side, who followed up Premier League victories over Fulham and Sheffield United with a 2-1 win away against Crystal Palace last weekend, courtesy of a 91st-minute winner from Harvey Elliott.
Liverpool capitalised on Arsenal's defeat at Aston Villa to leapfrog the Gunners to the top of the Premier League table, and before the Reds prepare for mouthwatering clashes with Manchester United and Arsenal in their next two top-flight fixtures, they must shift their focus to their final Europa League match with Union SG, as they attempt to round off the group stage in style.
Klopp's side enter Thursday's contest having won 15 of their last 17 group-stage matches across the Europa League and Champions League, scoring 50 goals in the process, while they are also unbeaten in all five of their previous European visits to Belgian, so confidence will be understandably high heading to Union SG.
Union SG Europa League form:
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Union SG form (all competitions):
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Liverpool Europa League form:
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Liverpool form (all competitions):
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Team News
Union SG have a clean bill of health heading into Thursday's fixture, but they will have to cope without midfielder Charles Vanhoutte as he will serve a one-match ban due to an accumulation of yellow cards.
The absence of Vanhoutte could see Mathias Rasmussen handed a start alongside Lazare Amani and Cameron Puertas, who both started in the engine room in the reverse fixture against Liverpool.
Top scorer Mohamed Amoura netted brace in last weekend's win over Charleroi, increasing his goal tally across all competitions to 13, and he is expected to retain his place in attack alongside Gustaf Nilsson.
As for Liverpool, Alexis Mac Allister is facing a race against time to set up a reunion with brother Kevin Mac Allister - who is expected to start in defence for Union SG - as he is nursing a knee injury sustained against Sheffield United last week.
The Reds will definitely be without five players in the form of Joel Matip (knee), Diogo Jota (muscle), Andrew Robertson (shoulder), Thiago Alcantara (hip), Stefan Bajcetic (calf) who require more time in the treatment room.
Klopp is expected to rotate his side who have already secured their place in the last 16, so the likes of Caoimhin Kelleher, Joe Gomez, Ibrahima Konate, Curtis Jones and Ben Doak will all be pushing to start, while star men including Virgil van Dijk and Salah - who scored his 200th goal for Liverpool against Crystal Palace last weekend - could be given a rest with one eye on Sunday's clash with Man United.
Union SG possible starting lineup:
Moris; Mac Allister, Burgess, Machida; Castro-Montes, Amani, Rasmussen, Puertas, Lapoussin; Amoura, Nilsson
Liverpool possible starting lineup:
Kelleher; Gomez, Konate, Quansah, Tsimikas; Gravenberch, Endo, Jones; Elliott, Nunez, Diaz
We say: Union SG 1-3 Liverpool
The onus is on Union SG to take the game to Liverpool on home soil in their quest to secure a top-two finish, and Thursday's contest may be their best opportunity to get the better of the Reds, who could potentially field a much-rotated side.
Nevertheless, the lineup that Klopp selects should still be strong enough to outscore their Belgian counterparts en route to claiming all three points and completing Group E on a positive note.
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