Tottenham midfielder Dele Alli could face a three-match ban after footage appeared to show him punching West Brom's Claudio Yacob in the stomach.
The PFA young player of the year made contact with the Baggies midfielder during a first-half set-piece in Monday's 1-1 draw.
The Football Association might act retrospectively after studying the video and rule his action was violent.
Monday's result dealt a blow to Spurs' Premier League title hopes.
Tottenham manager Mauricio Pochettino said he had not seen the Alli incident but added: "Sometimes the opponents find him and try to provoke, they know he has a strong character and may react."
The standard punishment for violent conduct is a three match ban.
Second-placed Spurs are seven points adrift of Leicester with three games of the season remaining. The Foxes can win the title on Sunday with victory over Manchester United.
Alli has been hugely influential figure for Tottenham in his debut season. The former MK Dons player has scored 10 goals so far and has formed a strong partnership with lead striker Harry Kane.
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