Defeat in Saturday's third encounter with the All Blacks at Eden Park would confirm the Lions' worst set of Test results since 1983.
But Thomas insists it is not a time to throw in the towel, even though New Zealand hold a 2-0 series lead, having racked up 69 points and seven tries, including last week's 48-18 masterclass in Wellington.
"At the end of the day, we lost by 30 points, but it felt quite harsh, given the way we performed," said Thomas.
"If you go back, obviously, I would like to have won the first game of the series, but it is important now for the Lions that we go out on Saturday and try and get a victory.
"For us as players, we've bonded well and it has been an amazing experience. Yes, we want to do it for the Lions history, the jersey and everyone else, but also I want to do it for us as a group of people together.
"It would be great to give something back to us as players. The guys realise they can do something pretty special [on Saturday], even though we have lost the series.
"By sticking our heads in the sand, there is no way we are going to achieve it. Our training has been a lot lighter this week, and no-one has backed down from anything.
"I think we learnt some lessons from the second Test. I think we have got to be a little more clinical and keep hold of the ball a little bit more, but I also feel we couldn't have done that much more either.
"I was proud of the way the guys played. At the end of the day, we were beaten by a better team, so we have got to go out with the same attitude. I don't think there is much more we can do, and hopefully that will be enough."