Manchester United's comfortable 3-0 win over Sunderland last Sunday was remembered not for the three points, but for an incident involving Jose Mourinho and Michael Carrick.
In the final few minutes at the Stadium of Light, United fans were in full voice and could be heard singing: "Diego, wooah, Diego, wooah."
Their chants were in honour of Diego Forlan, who spent two years at the Theatre of Dreams from 2002-2004 and is fondly remembered for his brace away to Liverpool.
Mourinho was left confused by the song, though, so much so that he was caught on camera turning to Carrick and asking: "Who is Diego?"
Carrick then explained how United's fans were singing about Forlan, to which the Portuguese appeared to ask: "Why?"
Check out the hilarious incident below.
Mourinho could hardly be blamed for not knowing which Diego United fans were singing about, nor for asking why that was the case.
Forlan spent just two years under Sir Alex Ferguson and his spell was quite disappointing. As mentioned, the brace against Liverpool was his best moment at the club.
The Uruguayan has now reacted to Mourinho not knowing who he was or why his name was being sung and explained how he's surprised more people don't say the same.
"Soon after the match ended, I received messages which showed television footage of Jose Mourinho turning to Michael Carrick to ask who Diego was," he told The National, per Manchester Evening News.
"United fans were singing about me in the away end, something which I cannot believe still happens. I loved my time at United and had a good relationship with supporters.
"But I am sure there are many others who say exactly the same, some of them who had more successful careers at the club than I had. And they do not get their names sung.
"It is all very flattering, but I love that catchy little song: 'Diego, wooah, Diego, wooah, he came from Uruguay, he made the Scousers cry'.
"People still come up to me wherever I am in the world and remind me of two goals scored in a Premier League match 15 years ago more often than they do about my goals which saw me as the top scorer in the 2010 World Cup."
Well, at least he's honest. Forlan appreciates he didn't make a big enough impact during his two-year stint at United and that there are some former players more deserving of a song about them.
It's amazing how one single moment of brilliance can turn you into a cult hero.News Now - Sport News