DC United head coach Wayne Rooney substituted one of his players following allegations he used a racist slur against an opposing player in Sunday's match against Inter Miami.
United took on Inter at Audi Field, with Miami picking up a dramatic 3-2 victory thanks to an extra-time winner from Gonzalo Higuain.
But the result was overshadowed by allegations that DC United forward Taxiarchis Fountas racially abused Inter defender Damion Lowe during the match.
Advert
In the 59th minute, Fountas and Lowe were involved in an altercation which resulted in DC striker being booked along with Miami defender Aime Mabika.
Play was suspended for several minutes as referee Ismail Elfath consulted both teams' captains as well as Rooney and Inter Miami head coach, former Manchester United defender Phil Neville.
Play eventually resumed, with Fountas being substituted by the home side in the 66th minute.
Advert
After the final whistle, Miami defender DeAndre Yedlin claimed Fountas had used a racial slur during his altercation with Lowe and revealed that the visitors had refused to play until "something was done with that player".
Yedlin said: "Damion and another player got into a bit of a scuffle - as Damion walks away, one of their guys called him the n-word."
Inter boss Neville also claimed that Fountas had used the "worst word in the world" during his scuffle with Lowe.
Advert
"We need to address an issue that maybe in the past was swept under the carpet, but we're a club that is proud of our diversity and inclusion in our staff and supporters, and there is no place at all for racism on a football field or society," said Neville.
"A word was used that is unacceptable in society. It is the worst word in the world."
After the match, Rooney confirmed that an official complaint had been made the visiting team.
Advert
"There was a complaint, which I'm sure will get investigated. Not much more I can say," said the former England captain.
Fountas, meanwhile, has denied using the alleged slur, according to The Athletic's Pablo Iglesias Maurer.
The MLS has since confirmed it has launched an investigation into the incident.
"MLS has zero tolerance for abusive and offensive language and we take these allegations very seriously," read an official statement.
Advert
"An investigation into this matter will begin promptly. Further information will be provided upon completion of that investigation."
DC United confirmed they will "work closely" with the MLS and Inter Miami to resolve the issue.
A club statement read: "D.C. United are aware of the allegations involving a player during the match against Inter Miami CF.
"The club will work closely with Major League Soccer and Inter Miami to investigate the incident."
Meanwhile, Neville has praised Rooney for the manner in which he handled the incident.
"I must commend my players for keeping calm, I must commend the referee. In a really, really difficult situation, he followed the protocols set out by the MLS. And I must give massive respect to Wayne Rooney, for dealing it in the way that he did," said Neville.
"I've always known him as a class act. I think today he went up my estimations more than he's ever done, more than any goal he's ever scored."
Topics: DC United, Inter Miami, MLS, Phil Neville, Wayne Rooney, Football