Swansea are set to launch an investigation after their goalless draw with Reading was marred by booing and jeering outside the Liberty Stadium as both teams took the knee before kick-off.
The Welsh side will aim to get to the bottom of the issue after it happened for their second successive home game.
On the field Steve Cooper's Championship promotion hopefuls were left frustrated by a goalless stalemate as Royals goalkeeper Rafael Cabral produced a series of stunning saves.
But the big talking point came before a ball was kicked.
As both sides took the knee before kick-off in support of the Black Lives Matter movement, a loud series of horns and booing noises was heard from a group gathered outside the ground. It is unclear who the group were or what their motives were.
Cooper said: "I heard some noises but I couldn't tell what it was. Let's find out and the reasons behind it.
"In terms of taking the knee we are a club which has continued to commit to it."
Swansea will now look into ensuring the incident does not happen for a third time when they host Watford on Saturday.
Cooper's men were playing their first game on the new Liberty pitch. The old one had been ripped up before Christmas after it deteriorated badly.
Swansea had to settle for a point as they missed out on moving back into second.
Rafael was the man to deny the Welsh side time and time again. The Brazilian produced half a dozen superb saves and stopped Swansea's star man Andre Ayew in acrobatic fashion in either half.
Rafael had conceded 12 goals in five games in November during Reading's poor run, but he was outstanding here to earn his team a gritty point.
Reading manager Veljko Paunovic said he was aware of the booing pre-match but did not comment further as he did not understand the reasoning for it.
Instead he rightly hailed Rafael's display.
"He was man of the match for me and I am very happy with his performance," Paunovic said. "He is the pillar of our defence.
"We built our identity on defence at the start of the season and we are slowly getting that back.
"I was not upset with his (Rafael's) performances and I don't want to go into the past.
"We were organised and very brave but also lucky. The whole team did a great performance in defence."
Ayew took the blame for his team's draw and said: "We have lost two important points tonight. I'm very disappointed. One of my headers should have gone in. It's hard to take.
"I have scored a lot of important goals for this club and I should have scored tonight. If we want to get automatic promotion we need to bury chances in games like this."