Lionel Messi registered his 20th assist of the season as a lacklustre Barcelona maintained pressure on leaders Real Madrid with a 1-0 victory over Valladolid.
Chilean midfielder Arturo Vidal struck the only goal of the game in the 15th minute, firing into the net off the post after being played in by Messi, who now has 20 assists in the league to go with his 22 goals.
Barca failed to build on their early advantage and were forced to grind out the victory in the second half as Valladolid took the game to the champions.
Valladolid's forward Enes Unal forced Barca's goalkeeper Marc-Andre ter Stegen to stretch across goal and tip away his shot, moments after Kike Perez had missed the target from inside the area as the home side made a lively start after the break.
Ter Stegen was forced into action once again in added time to repel a shot from former Barca forward Sandro Ramirez as the visitors were left begging for the final whistle to arrive.
The scrappy victory moved second-placed Barca to within a point of Real Madrid, who can restore their four-point advantage when they visit Granada on Monday, while Valladolid remain in 14th place.
Should leaders Real beat Granada and follow that with victory at home to Villarreal on Thursday, they will be crowned champions for the first time since 2017.
La Liga round-up: Atleti boost hopes for third
Atletico Madrid boosted their bid to finish third with a 1-0 home victory over Real Betis.
Diego Costa came up with a 76th-minute winner after Atletico had defender Mario Hermoso sent off before the hour.
Celta Vigo remain in relegation trouble after letting an early lead slip to lose 2-1 at Osasuna.
Santi Mina converted Iago Aspas' 11th-minute cross to hand the visitors the lead, but Enric Gallego equalised midway through the first half.
Mid-table Osasuna snatched victory in the final seconds as Jose Arnaiz's header left Celta four points above the relegation zone.