Belgium take on Ukraine in the other game in the tightest of pools in which all four teams have three points, but Romania head the group going into the last round of fixtures and Iordanescu says his side will go all out for the win to stay there.
"We can’t control what people talk about, but we have full concentration on the game tomorrow," he told reporters on Tuesday.
"We are playing to qualify and we do want to finish first. If we win the group, at least theoretically, you have a certain advantage in terms of extra rest days and a (weaker) opponent.
"But the most important thing is to qualify, this is our main objective. This is a historic moment for the national team, a moment that is special and the greatest moment in our careers."
Romania brushed aside Ukraine 3-0 in their opening pool game but lost 2-0 to Belgium in their second. Slovakia, Iordanescu believes, will be a very challenging opponent too.
"Slovakia are one of the best organised teams at this tournament," he said. "I have studied them a lot in the qualification competition and here in Germany. Their coach (Francesco Calzona) has built a clear identity and a balanced team with experience.
"They have had an extra day of rest, but tomorrow we won’t care about tiredness or pressure, it is only the heart that matters. There is no other scenario for us, we want to qualify, no matter how."
Romania have reached the knockout rounds of the Euros once before, in 2000, and the chance to repeat that feat after 24 years will make the battle in Frankfurt a mental one as well as physical, according to Iordanescu.
"If you look at their statistics, Slovakia are a very precise team who have clear mechanisms and a very complex way of playing. Players who balance effort and technique, and they have three or four players who are the pillars of their team.
"They are a solid team, an emotional team, and it will be a mental battle. Both teams have the chance to qualify, but both have to keep their cool and react to what happens on the pitch."