The National Women's Soccer League (NWSL) said on Tuesday it had opened an investigation under its anti-discrimination policy after Chicago Red Stars defender Sarah Gorden said she and her boyfriend were racially profiled by a Houston security guard.

The incident happened after their goalless draw at Houston Dash on April 9 when a security official said her boyfriend "would be arrested if he came close" to talk to her following the match.

"At first I didn't realize this was a racial issue until I saw white @HoustonDash players surrounding the stadium talking closely to their family and we were the only ones targeted," she tweeted after the game.

My bf came to our game against @HoustonDash + after the game he came down steps to talk to me. We were immediately (before he was close 2 me)followed by security and told he would be arrested if he came close. Meanwhile white players were talking to white fam all over the stadium

— Sarah Gorden (@sarahlgorden) April 10, 2021

"This is just another reason why we kneel."

The NWSL said in a statement that an investigation into the incident had been launched on April 10.

"The league will have no additional comments regarding the current investigation prior to its completion and has asked the respective clubs to refrain from commenting further as well," the league added.

Red Stars assistant coach Scott Parkinson backed Gorden's account, saying the security guard was belligerent.

"I wasn't upset that it was one of our players," Parkinson wrote on social media. "I was upset that the only people being harassed were people of color."

The Dash issued two statements on the matter. The first said the team's staff was focused entirely on coronavirus safety, and apologized "for anything that may have created an impression to the contrary."

But on Monday, the team said its previous statement was "off the mark" and again apologised.

The team said it is "committed to creating a safe work environment, free from discrimination and harassment, and pending results of the investigation, will take any and all steps necessary to make sure that's the case."

Gorden has also received public backing from her club teammates, United States international Megan Rapinoe and the Black Women's Player Collective.

The NWSL said it would not comment further until the investigation is complete, and it has asked clubs not to comment.

Information from Reuters was also included in this report.