Perak striker Paulo Rangel was adamant his 79th minute header from Shahrulnizam Mustapa's free-kick had crossed the line before LionsXII goalkeeper Izwan Mahbud kept it out.
But assistant referee Hanif Rahman was unmoved, and referee Nafeez Wahab waved play on, leaving the 28-year-old Brazilian striker to hold his hands out in despair.
That "goal" would have given Perak a 2-1 lead, and would have almost certainly meant curtains for the LionsXII in their bid to make the Malaysia Cup quarter-finals.
Speaking after the LionsXII's 2-1 win at the Jalan Besar Stadium on Saturday night, Rangel told The New Paper: "It's a goal for sure, you saw it right?"
LionsXII fan Alfred Choong, who was seated near the corner flag, admitted: "Absolutely a goal. The assistant referee was not in line... But we deserved a bit of luck after being unlucky in our first three matches."
Both coaches said they couldn't see the incident clearly. Said Perak coach Azraai Khor Abdullah: "Maybe it didn't cross the line. If the referee is not sure, he can't award the goal.
"I can't say we were robbed. This is football. You win some, you lose some."
Izwan, who was in the thick of things, conceding a soft free-kick, attempting a free-kick, before providing the assist for Safuwan Baharudin's 85th-minute winner, said: "I was just focused on keeping out the shot.