Joao Felix scored a superb overhead kick as a much-changed Barcelona side battled to a 1-0 victory over relegation-threatened Cadiz in La Liga.
The Atletico Madrid loanee's acrobatic effort put Barca in front late in the first half and it proved enough to secure three points for the visitors.
Victory leaves Xavi's side second, eight points behind leaders Real Madrid who earlier won 1-0 at Mallorca.
The top two meet in El Clasico at the Santiago Bernabeu next Sunday.
With the second leg of their Champions League quarter-final against Paris St-Germain on Tuesday looming, Xavi made eight changes to the Barcelona side with three teenagers - Pau Cubarsi, Hector Fort and Vitor Roque - included in the starting XI.
The changes led to a disjointed performance with few chances created in the first half prior to Joao Felix's moment of magic.
After Marcos Alonso's corner looped up off the head of a Cadiz defender, the 24-year-old forward flung himself into the air for a bicycle kick and, despite the close attention of two defenders, found the bottom corner.
Fermin Lopez nearly doubled the lead before the break but, with goalkeeper Conan Ledesma beaten, Victor Chust made a crucial goalline block.
Barcelona had chances to cement the win in the second half but, having failed to convert them, Cadiz almost to made them pay when substitute Diadie Samassekou's thumping long-range strike drew a fantastic save from Marc-Andre ter Stegen.
But the away side held on to start a hugely important week in their season with a victory, while Cadiz stay 18th, three points from safety.
BBC