The Dutch led 2-0 after strikes from Georginio Wijnaldum and Wout Weighorst early in the second half but allowed the visitors back into the game with two goals in five minutes.
West Ham United’s Andriy Yarmolenko was afforded too much space on his left to score a superb curler on 75 minutes to make it 2-1, before Roman Yaremchuk headed home from a free-kick in the 79th minute.
But Denzel Dumfries popped up with an 85th minute header to earn the Netherlands all three points, with de Boer breathing a sigh of relief but wanting better.
“Sour, because we played dominant. You dont hope that your opponent will get opportunities through your own mistakes,” de Boer said post-game.
“You know Yarmolenko is left-footed, he’s famous for it. We have to defend it better, even if it was a great goal. It was not necessary.
“The second goal was a free-kick. Two players were too enthusiastic and that’s the reason why there was no offside given.
“We have to learn from these mistakes so hopefully next time they do not happen. The opponents always get opportunities, but you hope it will not happen because of your own faults. These two goals, I’m sure, were not necessary.”
The Netherlands are back in action on Thursday against Austria, who overcame North Macedonia 3-1 on Sunday.