The powerful centre pinpointed the high number of turnovers, especially in the first half, as pivotal to the game.
However, the straight-talking midfielder was in no mood to dwell on the defeat and promised fans that the squad would do everything possible to respond in the right manner against champions Saracens next Sunday.
"We know the defeat was of our own doing," admitted Rasmussen. "We will look back at the game and do the analysis in the week, but you can quickly identify that it was our turnovers that hurt us.
"You can't win an Aviva Premiership game when you are turning ball over like that. When you turnover ball you want to do that on your own terms, you don't want them to be getting on the end of it and then being put on the back foot and conceding points because of it.
"If you take away the turnovers we seemed to have them under control. The second half we dug in and showed character to try and put right what went wrong in the first half. We didn't seem to get the calls or bounce, though, so it becomes even more uphill.
"It's a long season and the great thing about rugby is that you have got next week to put it right," added Rasmussen. "You can come out and get the opportunity to put those things right, which I am sure we will.
"I know it's going to be a hard week for us all, we will be eager to get out there and put it right while having a go at the champions. You want to test yourself against the best and so we look forward to playing Saracens."
Rasmussen was tasked with keeping The Volcano - Lesley Vainikolo - quiet at Kingsholm and made his mark with a thundering early tackle to win back ball from the former England international.
However, the Warriors ace was still critical of his own display and vowed to get even better.
He said: "You want to gauge yourself against the best and Vainikolo is a very impressive man. The Volcano takes a bit of looking after, but I felt we kept him under wraps quite well. However, there are other parts of the game we didn't do so well.
"On a personal level, I'm not happy with the balls I put down and lost in contact. I will be doing all I can this week to be sharper and better next time."