Liverpool defender Glen Johnson will be out for around a month with a groin injury, British media reported Wednesday.

The 30-year-old tore his groin during the first half of Liverpool's 3-0 defeat against Manchester United at Old Trafford on Sunday and according to the Liverpool Echo newspaper, the England defender will be out for at least a month.

Johnson will undergo a scan to confirm the full extent of the injury, but he expected to miss Liverpool's hectic Christmas and New Year Premier League program.

Johnson has been repeatedly linked with a move away from Anfield, with his contract up in the summer and Liverpool yet to offer him a new deal.

The club reportedly want him to accept a substantial pay cut, but the defender is not keen to do so - particularly given that Roma are said to be willing to match his current wages.