Madrid, Jan 19 (IANS): Real Madrid's chances of winning the King's Cup knockout competition suffered a huge blow as they were beaten 1-2 at home by an impressive Celta Vigo in the first leg of their quarter-final tie.

Madrid controlled parts of the game, but were caught on the break by their rivals on Wednesday. They will now have to score at least two goals in next week's return leg away from home after their second defeat in two games after their 40-game ended away to Sevilla on Sunday night,reports Xinhua news agency.

After a goalless first half Celta took the lead through a 64th minute Iago Aspes goal, as the striker rifled home his 13th goal in 13 games from inside the Madrid penalty area.

Five minutes later Real Madrid were level as Marcelo's volley took a deflection to take the ball past Sergio Alvarez in the Celta goal.

The relief in the Santiago Bernabeu Stadium lasted just a minute before Celta left back Jonny's shot from the outside of the penalty area beat Kiko Casilla to curl into the back of the net to clinch the issue.

Earlier in the evening Deportivo Alaves took a decisive lead to second division side Alcorcon.

The game looked to be heading for a draw before Alaves striker Ibai Gomez, who only went into the game in the 88th minute, opened the scoring in the last minute of normal time.

The former Athletic Club Bilbao forward then netted a 92nd minute free kick to leave Alaves on the verge of a semi-final place, given that Alcorcon need to score at least three goals to have a chance of reaching the last four.