These two teams, Union Berlin and Union St Gilloise have already made history by getting to this stage and will meet for the third time in the Europa League this season.
Nigerian sensation Victor Boniface could make a return to the Union St Gilloise starting eleven later tonight in the Europa League.
Union St. Gilloise are visitors in Germany where they face their hosts Union Berlin in the Europa League round of 16 first leg on Thursday.
Boniface is in line to start for his Belgian club in that encounter after he was rested by his manager at the weekend in a league tie.
The 22-year-old may have missed out on the richest footballers in Nigeria list but has established himself as one of the country's standout performers in Europe following superb displays for his modest side this season in the domestic league and Europe.
Boniface started on the bench against Eupen at the weekend in the Belgian Jupiler with his manager looking to keep his start performer in Europe fit and fresh for the decisive game against Union Berlin in Germany.
He has scored three goals and assisted one in just five starts this season for Union St. Gilloise in the Europa League.
Union Berlin vs Union SG Europa League tie
This particular fixture will see two clubs who have already made history in the competition look to get the better of each other in a bid to extend their impressive runs.
Victor Boniface has been consistent for Union St. Gilloise since he joined the club.
Both Union Berlin and Union St. Gilloise have reached this stage of the Europa League for the first time in their history but will clash in the round of 16 to determine which of them will go further.
Berlin and Gilloise are no strangers to each other having already clashed this season during the group stages in Group D.
This takes us to the head-to-head
Union Berlin and Union St. Gilloise will rekindle their nascent rivalry when they take to the pitch later tonight in the Europa League.
As stated above, both teams have already clashed this season in the competition, with head-to-head shared one win apiece in the Group stage.
When both sides locked horns in the group stage, the away side sealed the win on both goals, with Nigeria’s getting his only assist when they clashed in Germany in the first encounter.
Form Guide
In terms of their respective forms, Union Berlin are in the best shape heading into the Europa League clash later this evening.
Berlin is unbeaten in the last six matches with five wins and a draw in the Europa League compared to three draws and two wins for Union Gilloise.
However, in all competitions, Berlin is without a win in their last two matches while Union SG ended a run of three consecutive defeats with a 2-1 win over Eupen at the weekend.
Prediction
This is a difficult game to call given these are REI sides who have proven to be evenly matched in the Europa League this season.
Therefore, while the home side seems to be in better shape heading into this one, I can't get my head off the results from the encounters in the group stage.
I want to sit on the defence for this one, but I will go for a slim win for the team with a 19-game unbeaten run at home, Union Berlin.
Key stat
Boniface’s Union St. Gilloise have not kept a single clean sheet in their last five matches.