Marcelino felt Cadiz made it difficult for Villarreal on the night despite his side’s 3-0 Copa del Rey victory over the Andalusians.
Leading 2-0 from the away leg, the Yellow Submarine found it tough to break down a resolute Cadiz defence in the first half at El Madrigal, before Manu Trigueros opened the scoring on 56 minutes and a late brace from Gerard wrapped things up.
“We wanted to go through against a Cadiz side that made it difficult for us, particularly in the opening 45 minutes,” Marcelino told reporters.
“They were very well organised but when we went 1-0 ahead it opened things up for us.
“I didn’t draw any conclusions from the game but I was able to see players who have not had many minutes for us, along with lads from the youth team.
“But I was satisfied with how they did and they showed great commitment,” he added.
Villarreal will now meet David Moyes’ Real Sociedad in the last 16 of the competition.