Koubek was appointed in December, following the dismissal of Ivan Hasek in October after a humbling defeat to the Faroe Islands, and the 74-year-old will make his international managerial debut in Thursday's playoff semi-final in Prague.
Irish media reported in January that Koubek spoke of Ireland playing simple and straightforward football and at Wednesday's press conference an Irish reporter asked the coach about the "primitive" label.
"I said that Ireland plays primitive football? You must have had a bad Google translator or something," Koubek replied.
"I never said that, never. Ireland have quality players, the Premier League and Championship play very good football. I never said they play primitive football, so don't put that on me."
The Czechs are well aware of Ireland's danger man Troy Parrott who scored five goals in his side's two wins over Portugal and Hungary which earned the Irish a playoff spot.
"What I've noticed is a big heart, Ireland have a big heart, a team with a strong mentality, so they are certainly a tough opponent," he said.
"But we will have that mentality too. That's the kind of match it will be.
"As for Parrott, he's riding a wave, he's in great form, things are going well for him. We know how he plays, the players have the information. So now we just hope we can limit him as much as possible and stop that wave."
Tomas Soucek was stripped of the captaincy after the West Ham midfielder was held responsible for the team ignoring Czech fans after his side's final group game, a 6-0 win over Gibraltar in November, but he is still a part of Koubek's squad.
"His career is magnificent, wonderful. He's hugely important," the coach said.
"Even if he doesn’t wear the armband for certain reasons you know, nothing changes in terms of his authority or his full value to the team."
The winner of Thursday's game will host either Denmark or North Macedonia in Tuesday's final.
