Vitor Roque found the back of the net for the first time for Barcelona in their initial game following manager Xavi’s announcement of his departure at the season’s end.
In the 63rd minute, substitute Roque, who had entered the match only a minute prior, directed Joao Cancelo’s cross into the net with a header.
Just four minutes later, Osasuna defender Unai Garcia was shown a red card for fouling the 18-year-old Brazilian Roque.
As a result of the win, Barcelona ascended to the third position, trailing La Liga leaders Girona by eight points.
This victory was particularly crucial for manager Xavi, who unveiled his departure plans following a 5-3 home defeat to Villarreal on Saturday.
The team faced an early setback when forward Ferran Torres tearfully exited the field due to injury after just five minutes.
Jules Kounde had two headed attempts over the bar from corners in the first half as the home team exerted control.
Following Roque’s goal, Osasuna, positioned 12th in the standings, had opportunities to equalize despite Unai Garcia receiving a second booking and being dismissed.
With 15 minutes remaining, Raul Garcia’s low shot struck the woodwork, and Barcelona goalkeeper Inaki Pena showcased a remarkable flying save to thwart Jon Moncayola.