Eddie Howe said he had to "control" himself after Newcastle's Champions League prospects suffered a major setback when Kylian Mbappé scored a contentious 98th minute penalty to earn a 1-1 draw for Paris Saint-Germain at Parc des Princes.
Referee Szymon Marciniak -- the man who refereed the 2022 World Cup Final -- awarded a penalty following the intervention of VAR after the ball struck the arm of Newcastle defender Tino Livramento following Ousmane Dembélé's cross.
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The ball had initially hit Livramento's chest before bouncing onto his arm, but Marciniak awarded the penalty after reviewing the incident at the pitchside VAR monitor.
Howe called it a "poor decision" but said that Newcastle must still believe they can qualify for the round of 16.
"Yes I do," Howe said, when asked if he felt a sense of injustice at the decision. "In my opinion it's not the right decision, but you fear the worst when it goes to the monitor.
"The speed of it and the ricochet, slowed down, looks different. The ball hits Tino's chest and then hits his arm, but it's not an unnatural movement.
"It was a poor decision with so little time left, but there's nothing we can do with it now.
"I have to control myself, that's my job. It doesn't do any good to lose control of what you think and say."
Newcastle can still qualify for the knockout stages if they beat AC Milan at St James' Park on matchday six and PSG fail to win away to Group F leaders Borussia Dortmund.
And Howe says that reality is one of the positives Newcastle can take from the bitterness of failing to win in Paris.
"I feel sorry for the players who performed so well in such difficult circumstances," Howe said. "We will look at the positives of what the players gave, they were totally committed to what we want to do.
"There were some massive performances and we are still in the competition, so we should look at the positives not negatives,
"It will take time for the emotions to turn to a positive, but the players have been absolutely outstanding."
PSG forward Mbappé admitted that Luis Enrique's team should have won the game after creating 31 shots over the 90 minutes.
"I try to be at my best level every night," he told TNT Sports. "I think I could have done more for my team. I had many chances and didn't score more goals.
"Too many chances. You watch many games and in the Champions League you have to score when you have the opportunity.
"It's hard when you see the game. What happened was we had so many chances to win. In football you can be so much better but don't win."