Barcelona won 1-0 at Celta's Estadio de Balaidos to stay four points clear of Real Madrid at the top of La Liga but had to battle hard to overcome the home side, while the referee also gave Luis Enrique's visitors some help.
Celta striker Nolito believed he should have had a penalty in the first half, while Orellana was shown a red card in the 87th minute after throwing a lump of turf at Busquets - 14 minutes after Jeremy Mathieu had headed the visitors in front.
But Berizzo refused to blame the referee for his team's defeat - their third in four games.
"When you lose it may seem an excuse," the 45-year-old coach told EFE.
According to Berizzo, Orellana's actions were "utterly irresponsible".
"We must leave satisfied because to impose your game against a team like Barcelona, full of fantastic players, we have to reinforce," Celta's boss continued.
"My players deserved more than the 0-1. This match has to be worth us to demonstrate that we can beat anyone."
But Nolito was left frustrated with referee Inaki Bikandi after he claimed Barcelona goalkeeper Claudio Bravo brought him down in the box just before half-time.
"For me it's a penalty, I'll have to see on TV," the Spanish forward said.
"I do not know if Bravo touches the ball but I'm sure he trips me."
On the other controversial moment of the match, Busquets insisted Orellana's red card was justified.
"He threw grass at me and the referee expelled him and that's it," Busquets told Sport.
"He apologized later."
