Ulster captain Johann Muller says the controversial Heineken Cup quarter-final defeat by Saracens will "haunt" his side for the rest of their lives.
Jared Payne's early sending off had Ulster on the back foot immediately but, despite losing Ruan Pienaar and Rory Best to injury, the Irish side were still only squeezed out 17-15.
Muller was stunned by Payne's dismissal for a high tackle on Alex Goode.
"I thought the red card was really, really harsh," the South African said.
"What I saw on the big screen was that Jared never took his eyes off the ball.
"Yes, the safety of the player is the most important thing, and we wish Alex all the best with his recovery. But the fact is Jared never took his eyes off the ball."
Muller, whose Ulster career will end in May without a Heineken Cup winners' medal to add to his World Cup winners' medal from 2007, acknowledged that Payne's fifth-minute dismissal left Mark Anscombe's side with a huge mountain to climb.
"I came in at half-time and said: 'Boys, if we pull this off it will be the greatest rugby achievement of my career and I've won a World Cup'.
"The character that each and every one of the boys showed to keep us in the match was incredible."
Muller pointed to Ulster's remarkable late efforts, with the 14 men putting over 30 phases together in the dying seconds before Saracens halted the pressure by winning a penalty.
"We possibly could have won in that 78th minute," he said. "It's one [Saracens] guy going offside or not rolling away or whatever the case may be.
"I'm so massively, massively proud but it's going to haunt us for the rest of our lives."
The Ulster captain did little to hide his bitter personal disappointment after playing his final European game for his adopted province.
"It's my last Heineken Cup game so obviously it's going to be emotional. The way that it happened is not the way I dreamt about.
"If we had lost fair and square, I would have taken it but to lose it in the way we did - by such a narrow margin after having fought so hard with 14 players for 75 minutes - hurts so much more."
In terms of the specifics of Payne's sending off, Muller felt the fact that Goode was forced off by the aerial collision did play a part in referee Jerome Garces's decision.
"I don't want to criticise him [Garces]. He made the call and we've got to live with it. [But] I do believe the state of the injury did have an impact on his decision.
"If he [Goode] had stood up [after the collision] maybe it would have been a different story."
Muller's team-mate Tommy Bowe bemoaned Ulster's failure to capitalise on a great chance for Heineken Cup success.
They were backed by a capacity 18,000 crowd at the redeveloped Ravenhill for the first time, while this is the last European campaign in which they call upon Muller and other departing forwards Joha Afoa and Tom Court.
"This was one of the best opportunities we were ever going to have, with the whole build-up and the fact we were playing Saracens, a side that we definitely had the beating of," said Bowe.
"It's going to be a tough ask without Johann and the likes of Tom Court and John Afoa.
"They are influential players in the team and are going to be a massive loss."