Leeds United have been told why they were fortunate not to have a player sent off during their defeat to Millwall in the FA Cup.

United were beaten 2-0 by the Lions in the fourth round of the world-famous competition on Saturday afternoon. The defeat means that Daniel Farke's men will give the Championship their full attention as they strive to return to the big time with Premier League promotion.

A brace from Femi Azeez handed Leeds a fourth-round exit from the FA Cup at Elland Road. However, one talking point came after Josuha Guilavogui was booked for a tackle on Millwall midfielder Casper De Norre.

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With no VAR used at this stage of the FA Cup, the decision from on-field referee Gavin Ward to hand Guilavogui a yellow card for the tackle remained unchanged. A former Premier League referee believes, though, that Guilavogui was lucky to stay on the pitch following the challenge.

Keith Hackett, who is also an ex-PGMOL chief, believes that Guilavogui should have been shown a red card for the tackle on De Norre. Hackett went on to issue a message to the PGMOL about punishments for similar challenges in the future.

"The PGMOL need to get their referees together to make certain that they all have a consistent application of law around the type of challenge we saw by the Leeds midfielder [Guilavogui] today," Hackett told Football Insider.

"There is no doubt, that challenge endangered the safety of an opponent. It did have excessive force."

Hackett continued: "As a result, a red card should be issued. Come on guys, let us see red cards issued for this type of challenge.

Leeds return to Championship action on Tuesday night when the travel to meet Watford at Vicarage Road. United have a two-point lead at the top of the table after Sheffield United's win over Portsmouth.