Manchester United's Champions League quarter-final clash with Barcelona is sure to bring back some painful memories for Sir Alex Ferguson.
Thirteen league titles and two Champions Leagues only go to highlight just how good a manager the Scot was, but he'll be disappointed that he didn't win Europe's highest club honour on a couple more occasions.
United lost two Champions League finals to Barca at the turn of the last decade, in 2009 and then again at Wembley in 2011.
And as revealed by Michael Carrick in his autobiography, it was that first failure that seemed to hit Ferguson the hardest.
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United would have become the first team to successfully defend the Champions League in its current guise had they won, but they went down 2-0 to Barca in Rome courtesy of goals from Samuel Eto'o and Lionel Messi.
And Carrick says the manager was livid after the game.
"The Boss was understandably angry and had a go at everyone," he wrote.
“'You need to have a look at yourselves and see if you can play at this level,' he said. Moscow [in 2008] was irrelevant.
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"We were Manchester United and the expectation was relentless.
"'You’ve let a good chance slip away here,' he said.
"The boss summed up exactly how I was feeling.
"After he finished, I just questioned myself again and again. Am I good enough?’
Carrick has called that defeat the biggest low of his career, and says he suffered with depression after the loss .
