Athletic Bilbao got their European challenge back on track with a 3-1 win over La Liga strugglers Granada at San Mames on Sunday.
Los Leones took an 11th-minute lead through Markel Susaeta, but they were pegged back three minutes later by Mehdi Carcela-Gonzalez's equaliser.
However, Inigo Lekue put them back in front on 33 minutes and Mikel San Jose sealed the win in the 69th minute as Bilbao returned to winning ways in the league – where they sit eighth, just a point adrift of the European places.
The Nazaries, meanwhile, remain three points off safety in 19th position after suffering their 14th defeat of the season.
Elsewhere, Sporting Gijon were denied the chance to climb out of the relegation zone after they drew 1-1 with Celta Vigo at El Molinon.
Moi Gomez fired the hosts in front from the penalty spot four minutes into the second half, but they suffered a setback when Jorge Mere received a straight red card 16 minutes from time.
Celta took immediate advantage of the extra man as they scored through Iago Aspas a minute later to secure a share of the spoils, although the point saw 18th-placed Rojiblancos move within a point of safety.
Earlier in the day, Espanyol arrested a two-match losing streak as they beat rock-bottom Osasuna 3-0 at the RCDE Stadium.
The Catalans got off to a good start when Felipe Caicedo opened the scoring on 17 minutes, while the 27th-minute dismissal of Oier made the visitors task that much harder.
Jose Manuel Jurado doubled the hosts lead at the start of the second half and Gerard Moreno wrapped up the win in stoppage time to take them up to ninth place, with Los Rojillos clear favourites for relegation.
Sunday's results in full:
Espanyol 3-0 Osasuna
Atletico Madrid 1-2 Barcelona
Athletic Bilbao 3-1 Granada
Sporting Gijon 1-1 Celta Vigo