Turin- Monaco coach Leonardo Jardim was furious after his side lost 1-0 to what he described as a "non-existent penalty" in their Champions League quarter-final first leg at Juventus on Tuesday.
The controversial decision will add to calls for the use of video replays as it was still not fully clear what happened, even after several repeats of the incident in slow motion.
The spot kick was awarded after Juve's Alvaro Morata got clear of Monaco's Portuguese defender Ricardo Carvalho as the striker chased a long ball forward from Andrea Pirlo.
Replays showed that Carvalho nudged Morata just outside the area but the Spaniard's fall took him inside the box and it was not clear whether there was further contact.
Czech referee Pavel Kralovec hesitated slightly, possibly consulting his goal line assistant, before pointing to the spot, while Carvalho was booked.
"It's a huge injustice, there was no penalty," Jardim told reporters. "We put Juventus in difficulties, but the result was based on a non-existent situation in an evenly-balanced match.
"The result was created by an incorrect decision by the team (of officials) that referees," he added. "This result is not a fair reflection of what happened on the field."
"All teams should have the same duties and rights," said the Portuguese coach, who has been widely praised for taking an apparently limited team so far.
Juventus manager Massimiliano Allegri said Carvalho was "the last man", but otherwise preferred not to get involved.
"I didn't see it, so I couldn't judge. It seems he was the last man," said the phlegmatic coach. "Whether it was inside or outside, I don't know."
There was a further surprise when midfielder Arturo Vidal, rather than forward Carlos Tevez, stepped up to take the kick.
Vidal has already missed two penalties this season, one in the 3-2 group stage win over Olympiakos Piraeus, and another in the 2-2 draw at Cesena in Serie A, when he could have scored a late winner.
Tevez and Vidal had wasted good first-half chances in Tuesday's game but the Chilean said he was still confident.
"We don't have a first-choice penalty-taker, it's a case of whoever has more faith at that moment," said Vidal.
"I felt I should take it and Carlitos agreed."