Spain strolled through the Group H match, breaking down the Saudi defence to move three goals ahead within the first half hour and easing their way to a comfortable victory.
“We decided to play with three centre-backs, so with five across the back and have a low block and to do as best we could possibly defensively," Donis said.
“But we had to be stronger and stop the ball. There was no single reason for what didn’t go well for us, but the key is we were not strong enough around the edge of our box.”
Lamine Yamal’s 10th-minute goal was an early blow, Donis added.
“Spain scored early with excellent pace, and this affected our morale. After that, we made a lot of mistakes when we had the ball at our feet.
“When a game is not going well and when you concede three goals very quickly, you feel insecure.
“Obviously we were affected, but you see that often in football. That is only natural.”
Donis insisted his defensive approach was the only way to try and stop the Spanish threat.
“We had a bad result today, but against one of the best teams at the World Cup, and it’s very difficult for us to digest. But I’m proud of my players for what they do every day, and I’ll never lose pride in my players, even after a poor result.
“We’ve already seen games at this World Cup that have ended in 6-0 or 5-1 scorelines. The most important factor for us is that we accept that we are going to be criticised, but I also expect those who criticised us to be realistic.”
Saudi Arabia are left with a single point from their opening two matches and conclude their group phase fixtures against Cape Verde in Houston on Friday.
Click here for more on Spain's win over Saudi Arabia
FIFA World Cup 2026
The 2026 World Cup is taking place from June 11th to July 19th in the United States, Canada and Mexico. The tournament features 48 national teams and is played at 16 modern stadiums.
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