The Basque side travel to the Nou Camp next weekend, but Llorente is aware that it is matches like the one against Sporting that will determine whether they stay up this season.
He told Marca: "It is nice to play against Barca, Real Madrid or Valencia, but it is these matches, like the one on Sunday, where the motivation has to be at 120% because they are finals.
"There are three points in play and that is all that separates us from Sporting."
Llorente is also hoping for a run in the side after finding his opportunities limited since the arrival of Philippe Montanier in the summer.
"I will continue to train as hard as I can because I owe it to the club; that is what they pay me for," he said.
"I would like to play more, like all of us who are in the stand, but only 11 can play and I have to wait for my chance."
Asier Illarramendi, Alberto de la Bella and Vadim Demidov remain out injured, but there is a huge boost for Sociedad in the return of Inigo Martinez after nearly a month out.
Sporting slipped to second bottom of the table with a 3-0 defeat to Villarreal on Monday, but manager Manuel Preciado remains confident that they can find a way out of trouble.
He told the club's website: "To say the first match in the second round of the season is life or death is an exaggeration but it would be foolish to deny the importance that it has. The team is tense and determined to turn the situation around.
"Our position was worse last season and the competition was more demanding so I remain as positive as I was at the start of the season that we can achieve our objective. We are three points from safety but also not far off mid-table."
Preciado is expected to make a number of changes to the side that lost to Villarreal. Diego Barral is suspended so Mate Bilic will come in to lead the line and Ivan Hernandez is expected to reclaim his place in central defence.