The midfielder has started the last two games though - an 8-0 win at Almeria in the Primera Division and a 3-0 Champions League victory at Panathinaikos - but expects Spain international Busquets to return for the visit of Real Madrid.
He said: "The fact I have been in the team for the past two games does not mean anything.
"I am clear that Sergio is the owner of the shirt due to everything he has done in recent years and I will try to do my best to help the team so they do not notice an absence as important as his."
He added: "Every day that passes I feel more comfortable here and closer to the levels I reached at other clubs.
"I have not played in a 4-3-3 formation that often and that, despite playing in my usual position, makes it a little different.
"Fortunately every day I can learn from my team-mates and my coach."