Both Spain and Germany have won the competition a joint record three times, but few ranked Luis de la Fuente's side as the strongest candidates for the trophy this summer.
However after breezing past reigning champions Italy and heavyweights Croatia in the group and dispatching Georgia in style in the last 16, Spain are now widely considered the tournament's most in-form team.
"They say it now, but three weeks ago nobody said that (we were favourites) about us," Real Sociedad forward Oyarzabal told reporters.
"We're sticking to the same idea and keeping on going in the same way, trusting ourselves, knowing we can compete against anyone.
"Now people think we're favourites we won't relax now, we're trying to prepare (for the Germany game) in the best way possible, with confidence."
Even within Spain before the tournament La Roja were not considered among the top contenders, despite winning the Nations League in 2023 to end an 11-year trophy drought.
Oyarzabal is certain the squad will not allow the new euphoria around the team get to them.
"We see the support, but we're also a bit removed from it," he continued, saying he was happy with Spain's isolated base camp in the southwest of Germany, near the Black Forest.
"Everything around us (here) can't be better, it's important to be here, in a place that can't be improved."
The 27-year-old believes Spain's squad is also impossible to improve.
"For me and for any us here, we've got the best national team possible," said Oyarzabal, who started in the group stage win over Albania.
"We've got the best players, the best team-mates. We're all for one, there's no divisions within the team, we all feel important."
Spain drew 1-1 with Germany in the group stage of the 2022 World Cup but in their previous meeting recorded a remarkable 6-0 victory in 2020 in the Nations League.
"A lot of time has passed since then, drawing conclusions from that game is not fair and wouldn't be good for us," said Oyarzabal ahead of the clash in Stuttgart.
"They are a great team... (but) we believe in ourselves and we're calm.
"On an individual level they have players who make the difference, who have had a very good year."
