London - England flanker Tom Johnson has been ruled out of the upcoming Six Nations Championship with a knee ligament injury, it was announced on Wednesday.
Stuart Lancaster, England's head coach, confirmed the Exeter back-row forward was facing three months out of action while speaking at the tournament launch in London.
The 30-year-old Johnson won the last of his five England caps against Australia in November.
Meanwhile, loosehead prop Alex Corbisiero will miss England's opening two fixtures, against Scotland and Ireland, while his longstanding knee injury is 'cleaned out'.
England will also be without Freddie Burns for at least the Scotland game at Twickenham on February 2, with the Gloucester flyhalf set to be sidelined for up to three weeks with knee ligament damage.
Lancaster added that it was "too early to tell" whether centre Manu Tuilagi, one of England's try-scorers in their dramatic 38-21 win over world champions New Zealand last time out in December, will have recovered from an ankle injury in time for the Calcutta Cup clash against the Scots.