Swansea City captain Ashley Williams and Leicester City's Riyad Mahrez clashed in the tunnel after the Foxes' 3-0 win at the Liberty Stadium.
The pair had to be separated outside the Swansea dressing room, and then Williams attempted to follow Mahrez on to Leicester's team bus.
Swansea City manager Garry Monk said he was unaware of the incident.
A Leicester spokesman said Mahrez did not try to enter the Swansea dressing room, but declined to comment further.
Williams and Mahrez came together during the first half of Saturday's match when the Swansea centre-back attempted to wrestle the ball from the Leicester winger to take a free-kick.
Referee Michael Oliver spoke to both players after the incident but did not show either a yellow card.
Mahrez had already scored twice by then, and collected his hat-trick in the second half to send Leicester two points clear at the top of the Premier League and heap more pressure on beleaguered Swans manager Monk.
After the tunnel clash, Williams brushed past reporters in search of the Leicester bus, but soon returned inside the stadium.