Liverpool skipper Steven Gerrard will be out for at least four weeks with a hamstring injury, leaving the English Premier League title chasers without the England star for the busy Christmas period.Gerrard pulled up with a hamstring problem during the 4-1 win over West Ham last weekend and limped out of the game in the 56th minute."Steven is, as reported, probably going to be up to about four weeks or so,” Liverpool manager Brendan Rodgers confirmed to liverpoolfc.com."So he’ll go through an extensive treatment programme over the next numbers of weeks and hopefully we can get him back that little bit sooner."But certainly at this stage, it was a four to six-week injury and we’ll see how we look with that.”Gerrard, who has helped steer Liverpool to second spot in the table, will miss the games against Tottenham, Manchester City, Chelsea, Cardiff City and Hull City.