Saudi Arabia coach Georgios Donis said his side cannot show Spain too much respect as they aim to repeat a shock victory over eventual winners Argentina at the 2022 World Cup.
Spain are under pressure to bounce back from a 0-0 draw against World Cup debutants Cape Verde, but face a Saudi side that themselves held Uruguay to a 1-1 draw in their opening game.
Donis only took charge of the 2034 World Cup hosts in April after short-lived reigns for Roberto Mancini and Herve Renard.
It was Renard who oversaw the famous win over Lionel Messi's Argentina in Qatar during his first spell as Saudi boss and Donis is hoping those memories can inspire a similar outcome in Atlanta on Sunday.
"It's nice to have miracles in football and we've seen it many times. We've seen it in the World Cup, we've seen it in other tournaments, we've seen favorites losing against underdogs," the Greek coach said at his pre-match press conference.
"It's great to have great memories in our national team such as the game against Argentina.
"We have to play against one of the best teams in the world and it's very important when you get to this sort of tournament and you have this sort of joy of playing against these teams to be able to enjoy those games, to respect the opponent but also not to respect them more than you should."
Spain's inability to break down the Cape Verdean defense highlighted La Roja's reliance on the brilliance of Lamine Yamal.
The 18-year-old only featured as a second half substitute as he is eased back to fitness after a hamstring injury.
Yamal is expected to take his place in the starting line-up on Sunday, even though he is not yet ready to play 90 minutes.
Donis hailed the Barcelona winger as the "biggest talent" in world football right now and did not hold back in recognizing that Spain are less effective without him.
"Spain is not the same team when Yamal is on the bench," added Donis.
"I think Yamal is maybe this period the biggest talent in the world. I think he started to replace Messi in Barcelona in the best way.
"I didn't see a player at this age to make this difference and to have this quality and to play with this maturity.
"For me the most important is not about the skills, but about the maturity and he knows what he can do every moment and that is the biggest difference."
