Sheffield United and Southampton have been fined £20,000 each for failing to ensure their players "conducted themselves in an orderly fashion".
Both clubs admitted breaching Football Association Rule E2 after tempers flared late on in Saints' 2-0 win.
John Fleck's foul on Saints' Che Adams sparked the confrontation.
Fleck was shown a yellow card, with team-mate Oli McBurnie and Southampton's Jannik Vestergaard then booked for their reaction.
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