Match ends, Celta de Vigo 2, Atlético de Madrid 0.
Celta Vigo deservedly beat Atletico Madrid to leave the Spanish champions seven points adrift of La Liga leaders Real Madrid.
Atletico - who beat Real 4-0 last week - never looked comfortable and trailed to Nolito's controversial penalty after he was felled by Mario Suarez.
A Celta handball moments before the foul angered Atletico, who hit the post through Antoine Griezmann in response.
Fabian Orellana added to Atletico's misery, driving in low from 12 yards.
Atletico are yet to host second-placed Barcelona, who they trail by six points, but the deficit to Real now looks a daunting one as the local rivals do not meet again.
So impressive after defeat at the Nou Camp on 11 January, Diego Simeone's side met Celta off the back of four successive league wins, culminating in the most comprehensive derby triumph since 2003.
But Los Rojiblancos were underwhelming throughout and had just 25% of possession in the opening period at Balaidos against a Celta side with one win in 11 league games before kick-off.
Simeone responded to the goalless first half by introducing midfielder Cani for Fernando Torres at the break, but seconds after Augusto Fernandez clearly handballed in midfield, Celta took full advantage when Nolito turned Suarez, forcing a foul.
The striker side-footed his eighth goal of the season coolly into the bottom right-hand corner from the spot and almost created a second for Joaquin Larrivey, who somehow failed to turn home from six yards.
Griezmann swivelled to shoot and force a smart save onto the post from Sergio Alvarez as Atletico faced defeat.
And when Orellana - impressive throughout - found space at the end of a neat Celta move, he took his time to drill across goal into the bottom corner, lifting his side to ninth in La Liga.
Elsewhere in La Liga on Sunday, Valencia moved fourth as Alvaro Negredo's penalty helped them beat Getafe 1-0 and Villarreal stayed sixth despite a 2-0 defeat at Rayo Vallecano.
- 1Álvarez Conde
- 20Gómez Sola
- 19Castro Otto
- 14OrellanaSubstituted forMina Lorenzoat 90+3'minutes
- 23Krohn-DehliSubstituted forLópezat 90+1'minutes
- 11LarriveySubstituted forHernándezat 76'minutes
- 7Mina Lorenzo
- 9Dias de Oliveira
- 1Moyá Rumbo
- 20Torres Belén
- 2GodínBooked at 57mins
- 14Fernández ArenasSubstituted forJiménezat 73'minutes
- 5Cardoso MendesSubstituted forSuárezat 34'minutesBooked at 57mins
- 19TorresSubstituted forGracia Calmacheat 45'minutesBooked at 63mins
- 22Gracia Calmache
- 24Giménez de Vargas
- Juan Martínez Munuera
- Shots on Target
Second Half ends, Celta de Vigo 2, Atlético de Madrid 0.
Foul by Pablo Hernández (Celta de Vigo).
Diego Godín (Atlético de Madrid) wins a free kick in the defensive half.
Substitution, Celta de Vigo. Santi Mina replaces Fabián Orellana.
Corner, Celta de Vigo. Conceded by Moyá.
Attempt saved. Fabián Orellana (Celta de Vigo) right footed shot from the centre of the box is saved in the bottom left corner. Assisted by Nolito.
Attempt saved. Diego Godín (Atlético de Madrid) header from the centre of the box is saved in the top centre of the goal. Assisted by Saúl Ñíguez with a cross.
Foul by Sergi Gómez (Celta de Vigo).
Guillherme Siqueira (Atlético de Madrid) wins a free kick on the left wing.
Substitution, Celta de Vigo. Álex López replaces Michael Krohn-Dehli.
Delay over. They are ready to continue.
Delay in match Sergio Álvarez (Celta de Vigo) because of an injury.
Offside, Atlético de Madrid. Juanfran tries a through ball, but Antoine Griezmann is caught offside.
Pablo Hernández (Celta de Vigo) wins a free kick in the defensive half.
Foul by Saúl Ñíguez (Atlético de Madrid).
Attempt saved. Mario Mandzukic (Atlético de Madrid) header from the centre of the box is saved in the centre of the goal. Assisted by Juanfran with a cross.
Foul by Augusto Fernández (Celta de Vigo).
Diego Godín (Atlético de Madrid) wins a free kick in the attacking half.
Substitution, Celta de Vigo. Pablo Hernández replaces Joaquín Larrivey.