LIVERPOOL, England, July 11 : Scrum-half Alex Mitchell has been ruled out of England’s final Nations Championship match next weekend against Argentina after sustaining a hamstring injury in the 73-8 thrashing of Fiji on Saturday.Mitchell has struggled with a similar injury through the season and lasted nine minutes after coming on as a second-half replacement for Jack van Poortvliet before limping off.“I don’t know at this stage whether it’s a recurrence of the hamstring injury he’s had a couple of times already this season, nor can I confirm the length at this early stage of how long he’s going to be absent for, but it looks like he won’t be able to be part of next week,” said coach Steve Borthwick.England finished the test at the Hill Dickinson Stadium with fullback Marcus Smith at makes