Depor, promoted back to the top flight at the end of last season, have found life difficult on their return to La Liga and have not won since August, a run of six games.
That sequence included a 5-1 thrashing at Barca's title rivals Real Madrid, another side whose set-up includes few surprises.
And, while Oltra is confident he can predict how Barcelona will play, he accepts that does not necessarily mean Depor are certain to take something off Tito Vilanova's men.
He told a press conference ahead of the Riazor clash: "The theory (on how to stop them) we know, but putting it into practice is not easy.
"Barcelona are familiar because they are a team that everyone watches, but they are also the most difficult to stop."
Oltra knows his side could spend long spells on the back foot, adding: "We know in advance that we will not be able to impose our style, we will not have the ball and we're going to have to do other things. But good teams are those who adapt to all circumstances and we hope we can do that.
"If we do have to lose I would rather we left a positive image of a daring team."
The departure of Pep Guardiola at the end of last season and the appointment of his assistant Vilanova prompted many to forecast a transitional period for Barca, but that has not materialised.
The Catalans sit level on points with Atletico Madrid at the top of the table, five points ahead of third-placed Malaga and eight ahead of Jose Mourinho's Madrid.
There have been claims Barca are starting to move away from the tiki-taka style employed so successfully under Guardiola, but Iniesta denies there has been any significant change.
He told the club's official website: "We are still playing the same way. I don't think we're more direct than we used to be. The team will improve as the season goes on.
"We have to go to La Coruna and get the three points, and then carry on doing the same."
Barca have been hit with injuries this season, especially at the back, and although there had been talk Gerard Pique would return this weekend it appears he may need an extra few days to recover from a foot injury.
Iniesta added: "We have had a lot of setbacks with the defenders and that hasn't given us the stability we need.
"The people who know most about that (Pique's injury) are the doctors. If he isn't ready to play, then that's because he can't. But even if he's not there, we'll still have a competitive team."