Union bounced back from their UEFA Champions League exit with Teddy Teuma scoring both goals as they defeated KV Kortrijk 2-1.
Last Tuesday, Union were dumped out of the Champions League after losing 3-0 to Rangers as the Scottish side managed to turn around the 2-0 defeat conceded in the first leg.
As a result, Union will be now playing in the Europa League group stages.
Teuma put on a commanding performance as he scored a goal in each half to help Union record their second of the season.
The Malta international converted from the spot in the first half before doubling the lead in the second half.
Union will now face Brussels rivals Anderlecht on August 28.