Jamie Carragher has revealed his frustration at the manner in which Xabi Alonso was sold by Liverpool – and blames former manager Rafa Benitez for not making more of an effort to keep the player.

The Spanish midfielder announced his retirement from the game this week after a glittering career in which he won the Champions League at Liverpool and Real Madrid, as well as successive Bundesligas with Bayern Munich.

Alonso began his career at Real Sociedad before moving to Liverpool in 2004, where he played an important part in two of Liverpool’s most famous victories: the heroic comebacks against AC Milan in the 2005 Champions League final and West Ham in the 2006 FA Cup final.

The midfielder was eventually sold to Real Madrid in a £30m move, despite sources close to the player saying he wanted to stay at Anfield, and Carragher has revealed his frustrations at Benitez for not convincing Alonso to stay.

“I had no issue with Xabi wanting to join Real — for Spanish players that is the pinnacle — but I couldn't understand why Benitez didn't hold out an olive branch to sort things out,” Carragher told the Daily Mail.

“Benitez had his best team in five years at Anfield. We were close to having a team that could win the Premier League and perhaps reach another Champions League final. Why did he have to continue the fight with Xabi? He had won the initial battle by getting the upturn in his form.

“What's more, Xabi was under contract, so Liverpool didn't have to sell. They proved that the same summer when not letting Javier Mascherano join Barcelona. But the writing was on the wall for Xabi and things were never really the same after he left.”

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Alonso proved an immediate success at Real Madrid, where he displaced Guti in the club’s starting XI. Readers of Marca voted him into their La Liga team of the season and he was also nominated for Spain's midfielder of the season award.

He would go on to spend five seasons at the club, helping the club to win La Decima in his final campaign in Spain, before leaving to join Bayern Munich in 2014.

Alonso played a key part in the Miracle of Istanbul (Getty)

Surprisingly for a player of his pedigree, Carragher also revealed that when Benitez first considered selling Alonso at the end of his first season with the club, to replace him with Gareth Barry, only two clubs were interested in signing him.

“He was a strong character, loved by the fans, so when Benitez wanted to sell him in 2008 there was uproar and there was an episode during a pre-season game with Lazio at Anfield when the Kop sang 'You can stick your Gareth Barry up your a***' about his potential replacement,” wrote Carragher.

Benitez wanted to replace Alonso with Gareth Barry (AFP/Getty)

“Rafa's intention was to off-load Xabi for £30million and buy Barry for half that price. The appeal of Barry was that he was English and could play in two or three positions. But, believe it or not, only Juventus and Arsenal were keen to take Xabi.