Netherlands captain Virgil van Dijk admitted that his side had considerable room for improvement despite opening their World Cup campaign with a 2-0 win over African champions Senegal on Monday.
"We won but we also know that we can and must do better," Van Dijk said after the Netherlands needed late goals from PSV Eindhoven forward Cody Gakpo and Ajax midfielder Davy Klaassen to come out on top in the Group A clash at Doha's Al Thumama Stadium.
"Going forward we sometimes tried to force things, and we too often left ourselves exposed to Senegal's counter-attacks," he told Dutch broadcaster NOS.
"That is an area in which we will need to improve because it is an art that our next opponents, Ecuador, are very good at.
"But I am optimistic because I feel we are going to get better."
The Netherlands are level on three points in Group A with an Ecuador side who beat hosts Qatar 2-0 in the tournament's opening game on Sunday.
Liverpool star Van Dijk was making his major tournament debut on the occasion of his 50th cap, while Dutch coach Louis van Gaal handed a first cap in goal to Andries Noppert.
The giant Heerenveen shot-stopper excelled with a string of second-half saves, with the pick coming from Idrissa Gana Gueye's half-volley.
"It was a boyhood dream for me to play at a World Cup but I never thought it would be possible," Noppert told NOS.
"It was really special when the goalkeeping coach Frans Hoek told me on Friday that I was going to play.
"The closer the game got, the more tense I became, but it was a healthy tension.
"Even in club football I have never played at international level, but you have to start someday."