Porto’s Casillas capture a coup after Danilo and Martinez moves

Helton, who hails from Brazil, has done well to bridge the cap between Baia and St Iker but, at 37 and unable to ever really establish himself in the Samba Boys national set-up during his career, his days are numbered.

Instead, Casillas’ main competition, and that is all it is likely to be, at Porto could come from Turkish custodian Sinan Bolat, who spent last season on Galatasaray’s bench during a loan spell in his homeland.

In front of him, a back four containing centre half pairing Bruno Martins Indi and Diego Reyes, plus Alex Sandro and whoever replaces Danilo at right back, looks strong and solid.

Shielding the Dragons defence should be French anchorman Giannelli Imbula, who cost €20m but plugs a big cap left by Brazil destroyer Casemiro returning to parent club Real after an impressive loan spell.

Casillas is thus a key component of a six-man strong rearguard that allows a box-to-box midfielder in Hector Herrera or playmaker in Juan Quintero to support the front four.

Names to watch out for in attack include Cameroon striker Vincent Aboubakar, former Derby County loanee Alberto Bueno, Algeria international and 2014 African Footballer of the Year Yacine Brahimi, and Ricardo Quaresma, who once had a brief stint with Chelsea. Winger Cristian Tello continues his spell at Porto from Barcelona too.

All of this adds up to make the Dragons deadly adversaries on both domestic and European fronts. Lopetegui’s second season in charge of Porto should thus yield some silverware, and expect Casillas to play an important part in any success in what is a new venture.