Ibai Gomez finished off a wonderful Alaves counter attack deep into stoppage time to get his side the three points at Real Valladolid.
The hosts were the first to threaten after fifteen minutes but winger Keko Gontan was unable to keep his close range header down and the ball flew over the bar.
Almost immediately, Alaves went down the other end with a long ball floated to the back post where John Guidetti managed to get his head to the ball. Unfortunately for the Basques, the Swede couldn’t direct his header back into the path of Jonathan Calleri with Jordi Masip grabbing it.
It was an extremely scrappy half of football in truth with the only other real attempt on goal falling the way of Alaves. Jony cut inside from the left before firing a low shot on goal but it zipped just past the right hand post.
The second half began in the same way but just before the hour mark, Alaves really should have went in front.
John Guidetti found space at the back post but he spurned a glorious opportunity as he nodded wide from two yards.
He went close again five minutes later but his powerful effort from the edge of the box was held well by Masip.
The game was opening up by this point and Valladolid could have taken the lead but Toni Villa’s cross just evaded the reach of Duje Cop and Javi Moyano.
Ibai Gomez was next to go close for Alaves when he let fly from outside the box but his fierce strike was caught at the second attempt by Masip.
The frantic attacking spell continued with the hosts awarded a free-kick which Michel whipped just over the bar, with the ball clipping the roof of the net.
With ten minutes left however, the best chance of the game came and went. Keko was sent through one-on-one with Fernando Pacheco but his tame effort was stopped by the away keeper before penalty kick claims were turned down in the aftermath.
That miss would come back to haunt the newly promoted side as deep in stoppage time, Alaves struck. Jony raced down the left and his cutback may have missed Mubarak Wakaso but it was met by Ibai Gomez who drilled the ball into the bottom corner of the net to give the Basques their second win on the bounce.
Real Valladolid: Masip; Moyano, Olivas, Calero, Nacho; Keko (Ivi, 81), Anuar (Herrero, 67), Borja, Villa; Plano, Unal (Cop, 63)
Alaves: Pacheco; Aguirregabiria, Laguardia, Ximo, Duarte; Ibai, Brasanac (Manu, 80), Wakaso, Jony; Guidetti (Twumasi, 74), Calleri (Burgui, 63)