He attempted to play down his side's chances by claiming Romanian teams simply do not have the mentality to build on positive results.
"I hope that's the case," Smith smiled.
"We want to try and win the game tonight and that's all that matters to us.
"We have to show the way we played in the last game wasn't typical of our performances. Certainly, we played better in the other two games than we did in that game at Ibrox."
Rangers currently prop up Group G with just a single point from their opening match in Stuttgart, with 4-1 defeats against both Sevilla and Unirea leaving them in a precarious position.
Defeat in Bucharest would spell the end of Rangers' hopes of qualifying for the knockout stages and, for that reason, Smith refused to look beyond tonight's match.
He said: "We were asked at the end of the last game how we felt about qualifying and, after the way we played in the last game, we can't look any further than this game.
"To take something from this game will be vitally important for us and we will attempt to do that and it will have to be a far better performance than in the previous match."
Rangers skipper David Weir believes a lack of European football last year - they crashed out of the Champions League at the qualifying stage to FBK Kaunas - could be behind their sluggish start this time around.
But he warned they will have to get to grips with the competition again quickly - or forget about progressing to the last 16.
"We've got to adapt to it and get better at it," he said.
"We didn't have any European football last year so it's new to us again and we've got to learn quickly because if we keep getting bad results we will be out of the competition.
"It's something we have to learn very quickly. I don't think anybody can tell us how to do it, we've got to work it out for ourselves.
"We just need to play better than we did in the last game. We know if we play the same way as we played in that game, we will lose.
"An improvement in performance from every player is the most important thing."