“My sympathy with Karius is limited,” Hamann, 44, told magazine Sport Bild.
“We don’t have to discuss that he decided the final with his two mistakes.
“Something like that can also happen to a professional footballer.
“But what I didn’t like was his behaviour afterwards.
“To publically show his suffering after the final whistle was just as unnecessary as his tearful asking for forgiveness from the Reds fans.”
Karius’ double mistakes in Kiev allowed Karim Benzema and Gareth Bale to snatch goals for Real in a 3-1 defeat and the 24-year-old goalkeeper cut a sad figure as he tearfully applauded travelling fans after the final whistle.
However, Hamann was unimpressed with his fellow German.
“Liverpool fans forgive their stars just as well as any other, the anthem ‘You’ll Never Walk Alone’ is part of life out at the club,” said Hamann, who won the 2005 final with Liverpool.
“With one exception: when your ego doesn’t match your performance.
“Karius drives through Liverpool with the personalised number plates ‘LK1’ and makes waves in the city whenever he steps out.
“Having airs like that is something Cristiano Ronaldo, alias CR7, can pull off in Madrid, because he has won the Champions League five times.
“Someone like Karius has not achieved anything yet in his career and should be happy to have been given the chance by (Liverpool coach Jurgen) Klopp at a world-class club.”
Hamann is not the first former Germany international to criticise Karius, who left Mainz for Liverpool in 2016, after Lothar Matthaeus described his performance in Kiev as the “worst goalkeeping display in the last 20 or 30 years”.
However, Germany head coach Joachim Loew, currently in northern Italy for a World Cup training camp, sent Karius, who has yet to play an international, a text message of support following Saturday’s final.
British Police are investigating after Karius was subjected to death threats and vile abuse on social media by furious Liverpool fans following his costly mistakes in Kiev.
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