Exeter sold 7,800 tickets for the game and their fans made most of the noise, even when their team were eight or nine goals down towards the end of the match.
Niskanen says he and all the players and staff are appreciative of the support, especially as the journey from the West Country to Manchester was made more difficult by Storm Goretti.
Train services to and from the South West have been badly affected, while some road conditions for fans heading north had been treacherous.
“A big, big thank you for every single one of them,” he said.
“They kept on singing throughout the game. It mustn’t have been easy for them seeing goal after goal going in.
“But they kept on supporting us, even after the final whistle, they’re still there – they’re still applauding us, which was absolutely fantastic.
“They gave us so much energy, as they do every single week, but especially today when we came out to warm up and seeing them having the full side there was fantastic.
“We as a team are so disappointed that we couldn’t give them much to cheer about today.”
