Captain Casillas, who proudly hoisted the trophy four years ago, cut a forlorn figure after the 5-1 thrashing on Friday. (Agencies)
Coach Vicente del Bosque refused to pin the blame on his goalkeeper, who was outjumped for the third Dutch goal and gave away the fourth with a poor piece of control.
"When a team loses a match it's not just the performance of one single player, it’s a weakness in the total squad," Del Bosque said.
"We can't blame anyone, least of all Iker Casillas," he said.
With talented goalkeepers David De Gea and Pepe Reina sitting on the bench, Del Bosque is likely to face pressure to axe Casillas, who has won more than 150 caps.
As a boy, Casillas cost his family a fortune when the youngster forgot to hand in a pools coupon before a weekend when his father correctly forecast a series of draws.
But the goalkeeper has more than made amends over the years.
He has been a fixture between the posts as Spain have won the last two European championships, with that first World Cup title sandwiched in between.
He won the Champions League with Real Madrid as a teenager in 2000 and did it again in 2002, days before he turned 21.
Now 33, Casillas is no longer an automatic first choice at his club, but did play in their team which won the Champions League last month.
His rustiness was evident in that Champions League final when another error led to a goal for Atletico Madrid who led until the closing minutes.
It seems that rival players are becoming aware of the goalkeeper's new vulnerability.
"It was a bit of a gamble, but I had spotted Casillas off his line before the cross came in," Dutch striker Robin van Persie said of his spectacular header which tied the game up at 1-1 just before halftime.
Captain Casillas, who proudly hoisted the trophy four years ago, cut a forlorn figure after the 5-1 thrashing on Friday.