Krul came on for first-choice goalkeeper Jasper Cillessen in the dying seconds of extra time in Salvador, and the Newcastle player went on to save two of Costa Rica’s five penalties to book his side a place in the last four against Argentina.
“I think it is in the spirit of the game and an absolutely sensational decision by the manager,” Winterburn told Sky Sports News' World Cup Verdict.
“If you have a fantastic striker sitting on the bench you’d have no doubt that he’d come on to take one of the penalties and with the manager making this decision, it's justified by the result.”
Van Gaal will take over at Manchester United at the end of the tournament in Brazil, and Winterburn said the Dutchman’s leadership of his side in the pressurised environment of a World Cup suggested he would have no problems adapting to life at Old Trafford.
“He’s a big-name manager but what he’s showing us at this World Cup is that he'll make big decisions,” added Winterburn, who cited the substitution of captain Robin van Persie in the dramatic 2-1 win over Mexico in the last round as further evidence of Van Gaal’s willingness to back his own judgement.
“Van Gaal doesn't care: whoever’s in the team, whether they’re captain or not, he'll bring them off if he thinks they’re not performing at a level he deems acceptable.
“I think you have got to have that at a big club. You have to know the manager’s in control and is prepared to make the decisions, even if you don’t like it at the time, for the best of the team.”
But Winterburn said he felt Krul had gone “a little bit too far” with his attempts to put off the Costa Rica penalty takers during the shoot-out.
Krul spoke to several of the Costa Rica players before they took their penalties, leading to accusations of gamesmanship.
“People will look at it and say it’s a bit of sledging and it’s within the rules of the game because otherwise the ref would have stepped in,” said Winterburn.
“But I think the way he came up as the player was putting the ball in the spot, he was really in the faces. He was right in there and people might say you have to do what you can to get through to the semi-finals of the World Cup.
“I’ve done it myself and regretted it after but while you’re doing it, you're in the zone and you think it's just absolutely normal.”
And former Manchester United coach Rene Meulensteen reckons Van Gaal's attention to detail was vital in helping the Dutch to the penalty shoot-out success.
Although Meulensteen believes Krul’s appearance was unexpected, he is certain the Newcastle keeper would have been well prepared.
Meulensteen told Sky Sports News: “I can’t really see any risk because I’m 100 per cent sure this has been very well thought through and definitely communicated through with Tim Krul.
“He was ready for it. You could see that the moment he stepped on the pitch and the penalties were taken he was at it. He was engaging with the opposing players. I wasn’t sure whether that was the right thing to do but it had an effect and he was really ready to stop these penalties.”
Krul’s ex-Newcastle team-mate Steve Harper was full of praise for Van Gaal’s handling of the situation, after the Netherlands boss confirmed Cillessen would start the semi-final against Argentina.
Cillessen had made a vital save to deny Costa Rica the lead minutes before the substitution.
Harper said: “I think Van Gaal straight after the game coming out and saying why he did it, that Tim was the bigger goalkeeper and had more reach, immediately saying that Cillessen would be back in for the semi-final was just outstanding management.”