It was a realistic taste of what was to come with United being relegated from the Premiership just nine months later.
Blackwell returns to the KC tomorrow at noon and he said in the Yorkshire Post: "I hope we play better than we did that night (in 2003). We were embarrassing. It was our third pre-season game and that was the moment I realised we were in deep trouble.
"But things have changed since then. We are a club again now and stick together. We got relegated together and we will go back up together.
"I have had people over from Hull this week saying 'this is our biggest game of the season'. Motivation-wise, it means very little will be needed to get the Hull players up for it.
"This is the biggest game in Yorkshire so far this year and the KC Stadium is going to be a cracking place to be. It is a complete sell-out and that wasn't the case for Sheffield United's visit or Sheffield Wednesday's.
"But we have dealt with this every week all season long. We have gone to places where it has been totally hostile and it has not affected the players at all.
"Ours are the best away fans in the country. They are the loudest and I constantly hear in boardrooms from opposition chairmen that 'your support is phenomenal'."