Real Madrid goal scorer James Rodriguez admitted his form had not been great lately after he scored in his team's 2-0 Champions League win over Roma on Tuesday night, a result which sent Los Blancos through 4-0 on aggregate to the last eight.

James has been targeted recently by fans and pundits at the Estadio Santiago Bernabeu who are unhappy with how their expensively assembled team has fallen 12 points behind Barcelona in La Liga, and were painfully defeated 1-0 at home late last month by local rivals Atletico Madrid.

Having been left out of Madrid's last two league games, the €80 million signing returned to coach Zinedine Zidane's starting lineup for the high-profile European competition and was whistled during a first half in which he often misplaced passes and lost possession.

However, during the second half the Colombia international netted a fine goal and he told Spanish TV station Antena 3 after the game that he understood the demands were high at a club like Madrid.

"There are days when things do not go for you, but we know that anything can happen in football," James said. "I believe all the fans want to see nice football and when things do not go for you, they have the right to whistle. We are at a club which makes demands of you every day, and we players are here for this."

James Rodriguez scored Real Madrid's second goal in Tuesday's win over Roma. Denis Doyle/Getty Images

Through recent weeks, James has always received the public support of his coach Zidane, and he said he was working hard in training to try and improve his form.

"[Zidane] looks after us all," he said. "I try to improve every day, so that things go well. You must keep training strongly every day. Every time you go out to play you must give everything, even though some days things do not go for you."

Cristiano Ronaldo got Madrid's other goal on a night in which Roma created many chances themselves, but visiting attackers Mohamed Salah and Edin Dzeko could not take any.

"The result was fair," James said. "Italian teams are strong at the back; that is why it was difficult for us at times."