Both sides have struggled with consistency so far this campaign with just one point separating them in mid-table but Bergara is all too aware of how important a win on Saturday would be.
He told Marca: "We are hungry, the whole week we have been very excited. It is special, it is an important day for everyone and therefore we are going to go out at out our top level.
"To win a game like this is key, to win would be a huge push for the rest of the year and it is a marked day when all the team goes out to die for the cause."
Sociedad have however been dealt a huge blow with the news that goalkeeper Claudio Bravo will be out for the next few months after breaking his right forearm and wrist in training, but Bergara is confident that understudy Enaut Zubikarai can ably deputise for the Chile international.
"Bravo is a player that has been playing every minute and at a great level, but we are conscious that we have a great second goalkeeper and we are convinced he will do well," he said.
Athletic look set to welcome back their number one in goal as Gorka Iraizoz has recovered from the knee injury that kept him out of the 0-0 draw with Malaga last time out, but Inigo Perez's continued absence should mean another start for Xabi Castillo at left-back and he is looking forward to experiencing the derby atmosphere.
He told AS: "The derbies are very special. It is clear that they are three points more, but it is not just another match because both teams love to win this game.
"In the league we are on a similar trajectory and I think it will be a very even derby.
"They start as the home side, but we are coming into the game in good shape, with a desire to do things and to win the game."