Isco was among the goalscorers in Wednesday's quarter-final first-leg tie at the Bernabeu, scoring Real Madrid's second goal in the 27th minute with a clinical finish from the edge of the box after Gareth Bale had already put Carlo Ancelotti's men ahead after three minutes.
Cristiano Ronaldo then added a third in the 57th minute, equalling the record number for UEFA Champions League goals in a season when he rounded goalkeeper Roman Weidenfeller to tap home his 14th strike of the campaign in Europe's premier club competition.
While Real's array of attacking talent will deservedly take the plaudits, Isco was keen to credit the role played by Real's defence and reserved particular praise for centre-back Pepe.
"It's a magnificent result. We're happy with 3-0, with keeping a clean sheet and taking a step towards the semi-finals," he told the club's official website.
"Pepe and the whole defence were a 10 out of 10. The result is more than deserved and we take a significant lead into the second leg."
Isco admits he was not expecting to start the match, but was thrust into action as winger Angel Di Maria was ruled out with illness.
"I was a little surprised to play," he added.
"Di Maria came down with something, but you have to be prepared and that's what happened. I have to show people and the coach that I can play in any system and position and I'm happy."
Having lost to Dortmund at the semi-final stage in last season's Champions League, Real are seemingly on course to exact revenge for the defeat.
But Isco stressed the importance of not being complacent, as he added: "You never know in football.
"Nobody imagined the Real Madrid result there last year. We're going to play like we always do and we hope to be in the semi-finals."
