Venter's ban means he can have no contact with his team during the final
Brendan Venter cannot coach Saracens in their Premiership final against Leicester on Saturday after losing his appeal against a 14-week ban.
Venter was handed the punishment by the Rugby Football Union for "making provocative and inappropriate gestures" during a match at Leicester on 8 May.
The independent panel ruling means the South African is banned from team interaction at Twickenham.
However, his suspension has been reduced from 14 weeks to 10.
The decision means Venter, a qualified medical doctor, can only resume match-day involvement with Saracens from 30 July.
The three-man appeal panel was chaired by Jim Sturman QC, Gareth Rees QC and John Brennan in London.
"The panel was impressed by Dr Venter's appeal for assistance with his conduct in the future and his desire to avoid future clashes with the authorities," read an RFU statement.
"We considered that the appeal against conviction had no merit but have reduced the sentence to allow Dr Venter and Saracens the opportunity to put this matter behind them and start next season with a clean slate."
Saracens chief executive Edward Griffiths said he was disappointed with the panel's final verdict.
"There is no question that Brendan Venter was given a fair hearing by the panel chaired by Jim Sturman QC," he said in a club statement.
"However, in our view the penalty that prevents Brendan from even attending the Premiership final at Twickenham remains entirely disproportionate.
Perhaps it's time for English rugby to be run like a modern professional sport and not a rural prep school
Saracens chief Edward Griffiths
"All the attention and energies of the club will now be focused on maximising the performance of the team, and the enjoyment of our supporters on Saturday."
The outspoken Venter was adamant he "didn't do much wrong" after he became frustrated with his restricted view of the action at Welford Road following Sarries' 32-23 away defeat against Leicester on 8 May.
"I did stand up in front of the fans, and when they swore at me I did stand for longer than I probably had to," Venter told BBC Radio 5 live on Monday. "It wasn't for five minutes, it might have been for a minute-and-a-half.
"I didn't swear at all, I didn't make any obscene gestures at all - so I struggle to understand what I did wrong.
"If I can't see again when I'm sitting there, will I stand up again? Unfortunately, I will."
The dispute has also seen a row break out between the club and the sport's governing body.
Griffiths hit out at the RFU, saying: "Perhaps it's time for English rugby to be run like a modern professional sport and not a rural prep school."
RFU chairman Martyn Thomas, who could yet take disciplinary action against Griffiths, responded angrily.
He said: "Nobody is bigger than the game of rugby and we're becoming increasingly concerned at the erosion of the core principles of the game."
After Venter's initial hearing the RFU released an 11-page statement, in which it observed Venter's "arrogant behaviour" during the hearing, citing his eating of biscuits and sweets as examples.
But Griffiths said on Tuesday that he believes the club has strong grounds on which to fight the RFU's original decision.
"Three things are categorically accepted even by the original hearing," said Griffiths.
"One is that Brendan didn't push anyone, second he didn't swear at anyone and third he didn't make any obscene gestures.
The only person to suffer is me, not the team
"Taking all of that into account we feel a 14-week ban that means he misses the showpiece of the year is disproportionate.
"We don't want to be provocative, we don't want to be the brash, naughty boys of rugby... but Brendan Venter deserves to be at the final."
The lead-up to the final has been overshadowed by disciplinary issues, with Tigers coach Richard Cockerill also under the spotlight after an outburst during Leicester's semi-final win against Bath nine days ago.
During that match, Cockerill banged a table with his fist, kicked at a wooden partition and mouthed obscenities.
And at Venter's disciplinary hearing a week ago, Venter's QC said in mitigation that according to newspaper reports Cockerill's behaviour was "more reprehensible", yet no disciplinary action had been taken against him.
Venter insists his team will cope without him at Twickenham.
"The only person to suffer is me, not the team," he said. "I'm the one who gets taken away the privilege of enjoying Twickenham and the whole day that goes with it."