Updated Tuesday, Oct. 2 at 7:03 a.m. ET

Golf Channel insider Tim Rosaforte on Tuesday's "Morning Drive" confirmed that Dustin Johnson and Brooks Koepka had to be separated in the European team room on Sunday night of the Ryder Cup. Multiple sources also revealed to Golf Channel that the incident occurred.

Original story:

U.S. Ryder Cup teammates and close friends Dustin Johnson and Brooks Koepka almost came to blows while visiting their opponent's team room after Europe's 17 1/2-to-10 1/2 drubbing of the U.S. side, according to multiple published reports.

Johnson and Koepka had to be separated, according to witnesses cited in an article in The Telegraph by longtime golf writer James Corrigan.

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The source of the friction was not known, and the dust-up was considered unusual because Johnson and Koepka appear to have a very close relationship. They often work out together at trainer Joey Diovisalvi's Joey D Golf Performance Center in Jupiter, Fla.

Johnson and Koepka partnered in the Saturday afternoon foursomes, when they lost to Justin Rose and Henrik Stenson.

Johnson's fiancee, Paulina Gretzky, was reported to have been close by when the alleged incident happened. One of the European players’ wives also was a witness, according to The Telegraph, which also said that "an insider" reported that she was “clearly shocked and upset by the nastiness, which was very threatening."