MADRID, Oct 30 (Reuters) - Spanish league champions Real Madrid Irun were beaten 3-2 away by Segunda B (third tier) Real Union in the first leg of their King's Cup last-32 tie on Thursday.

The game was only two minutes old when Juan Dominguez burst past Michel Salgado to score the opener and put the illustrious visitors on the back foot.

Real's Argentine striker Gonzalo Higuain levelled on a counter-attack soon after, but the game had to be halted when his team mate Ruben de la Red collapsed and was taken to hospital.

Dominguez was gifted a free header to put the home side back in front after 20 minutes, and Real had to wait until after the re-start before Argentine striker Javier Saviola struck a great equaliser.

Again the modest Basque club hit back when Goikoetxea found space in the area to net the winner in the 63rd, but it will take a massive performance from Real Union Irun at the Bernabeu to put the 17-times Cup winners out of the competition.

Third tier Poli Ejido scored the upset result of the first legs thumping Villarreal 5-0 on Wednesday, when 2007 winners Sevilla fell 1-0 at another third tier side, Ponferradina.

Return matches are scheduled for November12.