Former Liverpool defender Jamie Carragher has complained that some Manchester United fans are being "disrespectful" by criticising Sergio Ramos amid reports that the club are interested in signing the Real Madrid star.

It is believed that the Premier League outfit will enquire about the Spaniard's availability this summer.

Once it emerged that the 29-year-old was on United's radar, a number of their fans criticised the defender's poor disciplinary record of 19 sendings-off, which is the all-time La Liga record for red cards.

Despite Ramos's negative qualities, Carragher believes that the defender deserves more respect as he has won three La Liga titles, one Champions League trophy, two European Championships and one World Cup.

"I get a bit wound up by the criticism Ramos gets," Carragher told talkSPORT. "This is a fella who has won everything, he players for one of the best clubs in the world and one of the best international sides we've ever seen.

"He is rash at times, he has moments of madness and does get overly emotional in games, that's always been a problem for him, but let's not forget that it's a problem for Wayne Rooney as well.

"I'm not bothered about whether United sign him or not, or whether he'd be a good signing or not, but if he is not rated as one of the world's best players, who is? I think it's disrespectful - he's won nearly 130 caps for Spain. He's not playing for Mickey Mouse teams."

Reports have claimed that Ramos could be using United as a bargaining chip to get an improved contract from Madrid.