Spanish champions Atletico Madrid have fallen seven points adrift of La Liga leaders Real Madrid after they were deservedly beaten by Celta Vigo on Sunday.
Atletico, who beat Real 4-0 last week, never looked comfortable and lost to Celta 2-0.
Atletico trailed to Agudo Duran'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, the BBC reported.
Fabian Orellana added to Atletico's misery, as he drove in low from 12 yards to double Celta's lead.
Atletico are yet to host second-placed Barcelona, who they trail by six points, but their 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.
However, while they did not create clear chances, they had just 25 percent of possession in the opening period at Balaidos against a Celta side with one win in 11 league games before kick-off, the report added.