Who are Royale Union Saint-Gilloise, the surprise package of this year’s Champions League?

Arguably their best known player is defender Kevin MacAllister, who is the older brother of Liverpool midfielder and Aregentina World Cup winner Alexis.

Union's players train on the eve of the UEFA Champions League football match between Royale Union Saint-Gilloise and Newcastle United. Pic: VIRGINIE LEFOUR/AFP via Getty Images.

Founded in 1897 in southern Brussels, RUSG have one of the most decorated histories in Belgian football, winning 12 top-flight titles.

What’s noteworthy is the 90-year wait between their last two championship triumphs – smashing the record gap across the 10 top European leagues held by Blackburn Rovers.