Real Madrid have defeated Cadiz 3-1 in the first leg of their Copa del Rey last-32 match, but Rafael Benitez's men could face expulsion from the competition due to fielding an ineligible player.

Denis Cheryshev, who started for Real, was unavailable for the fixture after collecting three yellow cards for Villarreal last season in the competition, leaving him to serve a one-match ban.

The Russian fired the visitors ahead in the third minute of the match when James Rodriguez played him into space in the inside left channel before the midfielder sent his effort past Cadiz keeper Pol Balleste.

Rodriguez almost doubled his side's advantage when he turned on the edge of the box before striking a low effort towards the bottom corner, only to see his strike creep past the post.

In the second half, Rodriguez continued to cause problems for the home side as he won a free kick on the edge of the box, but his resulting effort was well saved by Balleste.

Benitez's men doubled their advantage when Casemiro released the run of Isco with a pinpoint pass and the midfielder lifted his strike over the on-rushing Balleste into the net.

Isco notched his second of the match to put the game beyond Cadiz when Rodriguez cut open the home side's backline with an incisive through-ball for the Spain international to latch on to before slotting his strike into the bottom corner.

Kike Marquez scored a consolation goal for Cadiz, but Madrid held out for the comfortable victory to leave themselves in a strong position ahead of the second leg in two weeks.

However, due to their reported infraction they face an uncertain future over their status in the competition, as Cadiz have until 2pm tomorrow to launch an official complaint against Real.