Bergwijn fired wide and hit the post in the second half with the teams level at 1-1 and Spurs paid the price for their profligacy as Roberto Firmino scored a 90th-minute winner.
Bergwijn, 23, was forced to limit comments on his Instagram page after a slew of abuse following the misses and Mourinho said no player at the club should face individual criticism.
“I don’t know what can I do apart from the player knowing that in this club we are all together,” the Tottenham manager said.
“I know that in some clubs, with some people, is the culture of ‘they lost or we drew but I won’. In here, no. In here, we lose, we win, we draw all together. So, he has us. And we have him. And basically it’s this.
“So in here, we don’t feel any individualised criticism. We never feel it that way. We always feel it’s always about us. So no problem.
“He’s one of my boys. Period. There’s no point for me to individualise. He’s a good professional, he works hard for the team. He gives everything he can. That’s it.”
Mourinho, whose side host Leicester on Sunday, also revealed that Benfica would decide if Gedson Fernandes will remain at Tottenham beyond next month.
Gedson, 21, joined Spurs on an 18-month loan deal from the Portuguese club last January but is yet to make an appearance this season and was left out of the club’s Europa League squad – a situation that Mourinho says left his confidence ‘broken’.
“He deserves all our respect and Benfica because as a friendly club deserves our respect,” Mourinho said.
“So what they decide is fundamental and what they decide will prevail. The situation is sad because he was out of the Europa League list and by being out of that list reduced immediately a chance of nine matches that we already played in the Europa League, where we rotated the players a lot and we can bring to the bench 12 players.
“To be out of these nine matches I believe that breaks confidence levels and even dynamics and routines and was very bad for him.
“By having in the Premier League only until now six guys on the bench and the keeper I think it’s normal you go for players with more routine and match fitness.
“So these six months become really, really bad for us and for him and on top of it he’s a kid, it’s incredible what I’m going to say, but since he arrived he didn’t miss one single minute of one training session so he becomes even in low levels of happiness or motivation he’s managing to be a very good professional.
“So hopefully better days will come for him and they will come for sure, with us or without us, but better days will come for sure.”
Mourinho expects Gareth Bale to be “fine” to face Leicester after the Welshman missed the defeat to Liverpool and draw at Crystal Palace through illness, while Erik Lamela has returned to group training but remains unavailable. Japhet Tanganga is still sidelined with a shoulder injury.
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