The Barca defender has protested against the treatment he has received from referees in La Liga this term, suggesting his punishments have been disproportionate to the fouls made
The 25-year-old defender was dismissed after receiving two yellow cards from referee Alberto Undiano Mallenco, the first for obstructing a free-kick and the second for a foul on Carlos Vela, in a match which saw the leaders beaten for the first time in La Liga this season.
The Spain centre-half, speaking to journalists after the game, regretted the red card but did not appear to blame the official for his decision.
"They were two isolated instances where the referee decided to give a yellow card, and that's that," he was quoted by Marca.
"We have to accept it. I don't consider myself a dirty player at all, but I was given my marching orders."
However, Pique later took to Twitter to imply that he was less than impressed with some of the decisions that have gone against him this campaign.
"Season 2012-13: 14 games played, seven fouls committed, five yellow cards, one red," he tweeted on the social networking site.
It was the sixth time that Pique has been sent off in his career, and despite the result against Sociedad Barcelona remain top of the table with 55 points from 20 games.