Gerardo Martino's men face a game against Villarreal just two days after Vilanova's passing - following a lengthy battle with throat cancer - was confirmed.
The assistant to Pep Guardiola during a period of glorious success at Camp Nou, Vilanova subsequently took over as first-team coach and led the Catalan giants to the Liga title with a club-record haul of 100 points in 2012-13.
His condition then worsened earlier this month and Barca released a statement on Friday confirming Vilanova's passing at the age of 45.
Players from both sides will wear black armbands during Sunday's match, which is set to be preceded by a minute of silence in Vilanova's memory.
Matters on the pitch will be secondary in light of the news, though Barca can follow up last weekend's 2-1 win over Athletic Bilbao, which ended a run of three straight defeats in all competitions.
Martino's side are four points adrift of Liga leaders Atletico Madrid, with four rounds of fixtures remaining, while Real Madrid are a further two points back but boast a game in hand on the top two.
"Messi is the best in the world. Everything that's been said is exaggerated and out of control," Dos Santos told Sport.
"You can't trust the form of Barca. The league is the only trophy they have left and they are going to throw everything at it."
