The Blaugrana midfielder insists that his side is still full of confidence in its methods, despite criticism in the press and a poor recent run of form.
The Blaugrana saw their unbeaten start to the season promptly ended at the Amsterdam ArenA before suffering defeat a few days later at San Mames.
The club returned to winning ways by beating Cartagena 4-1 in the Copa del Rey on Friday and the Spain international has stressed that his side is ignoring its critics.
"There are no doubts in the team," Busquets is quoted as saying by UEFA's official website. "When you lose there are things that you don't do well. But we have no doubts at all, about either the style of play or any player.
"In the world of football only the results are important. We have to stay outside of the criticism and keep doing the right things."
Barcelona faces Celtic at Camp Nou in the Champions League on Wednesday and Busquets says the recent experience against the Glasgow giant will help his club overcome its opponent.
"We have the experience from last year. Celtic have a very different playing style to ours and so I think that the sooner we score against them the better because if we don't, they will close up at the back.
"Although they might not be playing for anything, Celtic want to end on a good result and they will do everything to achieve that. The important thing will be for us to win."