Evangelos Marinakis was banned for five matches after the Football Association argued successfully that the Nottingham Forest owner had spat towards match officials in a “flagrant display of disrespectful behaviour”.

Marinakis, who denied the charge, was found guilty of improper conduct by an independent regulatory commission over the flashpoint that occurred after Forest’s 1-0 Premier League defeat against Fulham at the City Ground last month.

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The home side had been furious with the referee Josh Smith after he awarded Fulham a penalty on the advice of the VAR John Brooks, while also denying two Forest claims for their own spot-kicks.

In publishing written reasons for the ban, the FA confirmed the independent commission was “satisfied” that Marinakis deliberately spat on the floor as the referee walked past him “in a disrespectful and disgusting display of contempt”.

The Greek billionaire argued he was merely disposing of phlegm, caused by his cigar habit, and the incident was unintentional. His witness statement read: “As the officials approached he felt a cough coming and he coughed on the floor, down and to his right which was away from the path the officials were taking. He did not speak to the officials.

“He cannot now remember if any spittle left his mouth but if it did (and he does not challenge that some might well have done) it certainly was not aimed at the referee’s feet and did not hit anybody. He fails to see how coughing (where spit or phlegm can come out from any person) towards the floor in a relatively crowded tunnel is misconduct.”

However the commission rejected this defence, calling it “completely implausible”, pointing out that none of the officials’ statements mentioned coughing and CCTV footage of the tunnel backed that up. Dominic Adamson KC said the action was “an egregious display of disrespectful behaviour such as this fuels disrespect towards match officials”.

In his statement, the referee Smith said: “As I walked down the tunnel at the end of the match, Mr Evangelos Marinakis, the owner of Nottingham Forest, was stood on my left-hand side at the end of the tunnel. As I walked past him, he spat on the floor next to my left foot. ”

The assistant referee James Mainwaring added: “At the top of the tunnel, on our left-hand side, Mr Marinakis was stood. He did not say anything but as we approached him and was close, he spat on the ground in front of us.”

Adamson, who reviewed the evidence with Bradley Pritchard and Mick Kearns, concluded that Marinakis “deliberately spat in a disrespectful and disgusting display of contempt towards the match officials” and “it clearly amounts to misconduct” within FA rules.

“The FA submit that the spitting was ‘entirely unprovoked’ and ‘no match official should be expected to tolerate such a flagrant display of disrespectful behaviour’,” the panel stated. “We agree.”

Marinakis, who is also the Olympiakos owner, missed Forest’s 1-0 win against Crystal Palace on Monday and will be absent for games against West Ham United, Newcastle United, Leicester City and Arsenal.

In a statement released on Friday, Forest said: “An appeal has immediately been lodged against this decision in respect of both the liability and the sanction.”