Barcelona defender Gerard Pique has called Spain teammate Iker Casillas 'the best goalkeeper in the world'.

Casillas has been under pressure at both club and international level over the last 12 months or so following a series of high-profile mistakes and his form is now being seriously scrutinised.

However, Pique has backed his international teammate, and insisted that the collective must be blamed for Thursday's shock 2-1 defeat to Slovakia in Euro 2016 qualifying.

"He is a professional without a doubt – the best in the world in his position," Pique told reporters at a press conference.

"Having him as a teammate and as our captain is marvellous as far as I'm concerned. I don't think anything went right for anyone in particular against Slovakia."

Real Madrid stopper Casillas is expected to continue in goal for tonight's Euro 2016 qualifier against Luxembourg.