The inevitable happened following Manchester United's failure to finish top of Europa League Group E, with a heavyweight tie against Champions League dropouts Barcelona confirmed during Monday's knockout round play-off draw.
Two of the world's biggest clubs, who boast eight European Cup wins between them, will clash over two legs in February for a place in the last 16, with the winners already being touted as champions-elect.
Barca edge their head-to-record, having won six games to United's three, while four of their meetings have ended in draws, only one of which was a 0-0 stalemate.
Their upcoming meeting will be the first on a Europa League stage, which shows how far they have both fallen in recent years, but there will still be plenty of top talent on display and an intriguing touchline duel to keep an eye on between Erik ten Hag and Xavi.
The question is, will this United vs Barca tie be able to rival any of those from the past?
Below, GOAL provides a recap of their most memorable battles, from a classic at Old Trafford to a masterclass at Wembley from a certain Lionel Messi...