Midfielder Joey Barton has been suspended by Newcastle United.
Barton was sent off for a lunging tackle on Xabi Alonso in the defeat at Liverpool on Sunday - a challenge boss Alan Shearer described as "stupid".
The 26-year-old was also involved in a row with Shearer after the game, which has prompted the club to suspend him.
A Magpies statement said: "Joey Barton has been suspended from the club until further notice. The club will be making no further comment at this time."
Barton's dismissal against Liverpool means he misses Newcastle's final three games of the season because of an automatic Football Association ban, but his whole future at the club is now in doubt.
Gordon Taylor, chief executive of the Professional Footballers Association, has been in contact with Barton's advisor and insisted the player is aware of the severity of the situation.
"He knows himself it was a bad challenge, it was bad judgement, but he has apologised to Alonso, to the referee and to the manager," Taylor told BBC Radio 5 Live.
"He realises what he has done and his reputation has gone before him.
"The mood in that dressing room afterwards would have been a feeling of frustration with Newcastle battling against relegation and this is the last thing they need and Joey knows that as well as Alan Shearer.
"It is a case of everybody loses with this one."
Newcastle's statement claimed Barton will be suspended from the club until further notice but BBC Radio 5 Live chief football reporter Ian Dennis said there is a timescale.
"I can confirm the length of Barton's suspension is two weeks," said Dennis.
"Newcastle's disciplinary action is sure to include a hefty fine, probably two weeks' wages as well.
It was a stupid tackle and he deserved to be sent off
"Although Barton's suspension is just a fortnight it is unlikely the midfielder will return to the training ground ahead of what would be the final game of the season, which he is suspended for anyway.
"And while Shearer is at St James' Park I cannot see Barton playing for Newcastle again."
The Magpies are currently in the bottom three and in serious danger of being relegated.
Sunday's appearance was Barton's first since 28 January because of a foot injury.
It was only the ninth time the former Manchester City player, who has had a troubled career both on and off the pitch, has played this season.
Shearer was clearly angry after Barton's dismissal.
"I wasn't happy, I was bitterly disappointed at the way that happened," Shearer told BBC Sport following the game.
Barton will be banned from Newcastle United for two weeks
"I asked him to stay calm in the heat of the battle but it was a stupid tackle and he deserved to be sent off."
Barton, who has played once for England, was a controversial figure at Manchester City before joining Newcastle for £5.8m in 2007.
He has since started only 26 matches for the Tyneside club.
In July last year, Barton received a four-month suspended sentence for assaulting Ousmane Dabo in a training-ground incident while both players were at City.
Barton was banned by the FA for 12 matches - six of which were suspended - and fined £25,000 after admitting a violent conduct charge in relation to the Dabo incident.
But Taylor said while he understands time is running out for Barton, he hopes the midfielder will be given another chance.
"The business is full of people who you wonder if they will ever learn and its the same with Joey," said Taylor.
"He has worked hard with Sporting Chance clinic and then this has happened and it is one more time.
"Of course people will run of patience but you just have to hope that he will get there eventually as soon his career will be over anyway."
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