Netherlands coach Ronald Koeman is taking nothing for granted after his side sealed top spot in Group F.
The Dutch advanced with a 3-1 win over Tunisia. They now face Morocco in the round of 32 on Monday in Monterrey, Mexico.
Koeman is wary of the North African side, calling it a formidable test.
"I'm not sure if we are the favourite in the match against Morocco," Koeman told reporters. "It's a good team with a lot of quality, and they can score easily."
The coach brushed aside questions about a potential path beyond Morocco.
"We're going towards our real test, and that's what we're going to prepare for," he said.
Despite finishing the group with seven points and 10 goals scored, Koeman noted defensive concerns. The Netherlands conceded in each of its three group matches.
He identified areas for improvement, including better compactness and sharper transitions.
"We need to transition faster," Koeman said. "You never stop learning in football."
The Dutch will train at their Kansas City base until Sunday before traveling to Mexico.
Koeman acknowledged the upcoming hot conditions and praised the massive support from Dutch fans who filled the stadium in orange.
His focus is now entirely on the knockout stage.
"If you lose you go home and if you win you stay in the tournament," Koeman said. "And of course we want to go far in this tournament."