Neil Lennon has suggested that decisions he believes went against his Celtic side in their Scottish Cup semi-final were "personal".
The angry Celtic manager had earlier raced on to the Hampden pitch to have words with referee Euan Norris after the 2-1 defeat by Hearts.
Lennon sent first-team coach Alan Thompson to talk to the media.
But he later said on Twitter: "Feel so sorry for players and fans... I think it's personal myself."
Celtic felt aggrieved after Hearts were awarded a stoppage-time penalty, which was dispatched by the Glasgow side's former striker, Craig Beattie.
A Marius Zaliukas drive struck the arm of Joe Ledley before also appearing to brush the hand of Victor Wanyama.
"Referee told players he thought Wanyama handled," said Lennon, who already has three disciplinary cases pending with the Scottish Football Association, in his Tweet.
Ledley himself entered the online debate.
"Can't believe the decisions made on the pitch today. Was never a pen," said the midfielder.
"This sums it up, he thought it hit Victor's arm."
Ledley also posted a photograph of a tackle on himself by Ian Black, suggesting that the Hearts midfielder ought to have been sent off rather than being shown a yellow card.
Following Beattie's goal, Celtic claimed for a penalty when the ball struck the body of Hearts defender Andy Webster - and also when Ki Sung-Yeung was challenged by Ryan McGowan.
Thomson said: "If the referee sees theirs as a penalty then he has to see ours as a penalty.
"There's no justice in his decision-making."
Celtic had fought back to cancel out Rudi Skacel's opener through Gary Hooper with three minutes remaining, but the stoppage-time penalty ended their hopes of completing a league and Cup double.
"Decisions have cost us again," said Thomson.
"He's gave one that might have been might not have been and he hasn't given one that might have been, might not have been.
"So where's the consistency there?"
Thompson praised his own side's performance.
"I thought it was a good semi-final," he said. "The first half didn't open up because they sat in and got 11 men behind the ball and made it difficult.
"We had lots of possession without creating too much and then the second half opened up a bit and it was a good game of football.
"They frustrated us, but we are delighted with the way we played.
"The lads were excellent. I'm so disappointed for them after the efforts they've put in.
"Hearts have had a couple of long-range shots from outside the box, so they haven't really hurt us.
"But we've missed chance after chance - Ki's hit the psot twice with headers."
Striker Hooper appeared to adopt a deeper role with Kris Commons moving forward from midfield.
However, Thompson insisted: "It was the same shape as last week, with a four-man midfield and Hooper and Samaras up front."
The first-team coach said defeat had effectively ended Celtic's season on a low note.
"We've just lost a semi-final and the chance to finish the season with a cup final to look forward to," he added.
"That's the season done and dusted now.
"We've got five league games to go. We've already won the championship, so it's disappointing.
"We'll have to get over this one - it will be a sore one - and then we'll try to have a good summer and build towards the Champions League qualifiers."